Other Specialty Fields / Marine Applications

At sea, zippers have to withstand
salt spray, strong sun and high winds

Yacht canvas, water-sports apparel and life-saving equipment spend long periods exposed to salt water and sunlight. A metal zipper that lasts for years on land-based apparel can corrode and seize quickly at sea, and a zipper failure on life-saving equipment also puts safety at risk. This page covers zipper selection, waterproofing levels and validation tests for marine applications, along with specifications for KCC hollow-tube zippers, spiral zippers, plastic zippers and track-type waterproof zippers.

ImageZipper in use on a yacht sunshade or cockpit covermr-hero · 16:9

Spec summary | Recommended on this pageKCC · MARINE

Quick-release canvas: KCC hollow-tube zipperTube threaded through the tape, seated in the hull track
Main canvas zipper: CF10 spiral zipperLateral strength per inch 1000 N (Class E+)
Lower-load canvas areas: VF8, VF10 plastic zippers
Waterproof bags, dry bags: Track-type waterproof zipper #3, #7
Water-sports apparel: CF5, CF8, CF10 spiral zippers
Physical testing standard: BS EN 16732

Plastic Zipper series Spiral Zipper series Industrial Zipper

Lateral strength per inch: the crosswise force a closed zipper withstands per inch of width. Strength class per EN 16732; “+” means above that class

Marine environment

Marine zipper requirements for salt spray corrosion, UV, waterproofing and safe handling

Salt spray corrosion

In high-salt environments, metal sliders and teeth tend to corrode and seize, and a sunshade may then stop opening or closing. Marine canvas generally uses plastic zippers or spiral zippers instead; their teeth are POM resin and polyester respectively, and neither rusts.

Intense UV

Reflection off the water exposes canvas zippers to stronger UV than on land, and the exposure lasts year-round. Tape without a UV-resistant treatment loses strength noticeably after a few years. KCC can supply UV-resistant tape; please contact the KCC sales team for specifications.

Different waterproofing needs

Canvas and water-sports apparel usually only need to be water-repellent, while waterproof bags must hold out powerful water jets or even brief immersion. Choosing the waterproofing level by application avoids over-engineering.

Safety and handling

Life jackets must be quick to put on and take off one-handed, in waves and in the dark. Life jacket zippers usually have a large slider and must still open and close normally at low temperatures.

Quick-release canvas

Attach sunshades to the hull track with a KCC hollow-tube zipper

Yacht sunshades, cockpit covers and deck canvas join soft fabric to a rigid hull and are fitted and removed again and again. One side of the KCC hollow-tube zipper seats in the hull track and the other side is sewn to the canvas, so fitting or removing the canvas only takes opening or closing the zipper.

KCC product

KCC hollow-tube zipper (quick-release canvas)

KCC Industrial Zipper category page

One tape of the KCC hollow-tube zipper has a tube channel: a rigid tube is inserted, and the tape is then seated in the track groove provided on the hull. The other tape is sewn to the sunshade or canvas. Close the zipper and the canvas is secured in place along the track. The standard teeth are polyester; versions with metal or plastic teeth can be developed on request.

No grommetsNo grommet holes in the canvas, so no weak points around them

One-person fittingZip along the track to deploy; no tying off section by section

Rigid / flexible tubeRigid tube seats in the track; flexible tube bends to follow curves

Quick removalEasy to take off for cleaning, repair and off-season storage

Compared with other fastening methods

vs. grommets and lacingNo holes in the fabric, so no grommet becomes the starting point of a tear, and no lacing through each hole during installation.
vs. metal zippersPolyester teeth do not rust, which avoids the problem of metal teeth corroding and seizing in salt spray.

The KCC hollow-tube zipper is a specialty product and currently has no individual page on the KCC product site; please enquire for specifications. Track groove dimensions, tube diameter and material depend on the hull design; please provide track drawings for selection.

Cross-section of the KCC hollow-tube zipper: a rigid tube inserted in the tape channel seats in the hull track groove, and the tape on the other side of the teeth connects to the sunshade. Not to scale; the actual track profile and tube diameter depend on the hull design.

ImageHollow-tube zipper securing a sunshade, as installedmr-canvas-photo · 4:3

Other common methods (for comparison only; not KCC's recommendation for marine canvas)

Method	Installation	Main limitations
Grommets and lacing	Grommet holes punched in the canvas, laced to the hull hole by hole	Time-consuming; grommet holes become weak points in the fabric
Metal zipper	Same as a standard canvas zipper	Slider and teeth tend to corrode and seize in salt spray; not recommended for marine canvas

Selection by application

Zipper sizes and materials for yacht canvas, water-sports apparel and waterproof bags

The table lists common sizes and recommended KCC products for yacht canvas, water-sports apparel, waterproof bags and life jackets. Product names link to KCC product pages.

ImageYacht sunshades and cockpit coversmr-scene-canvas · 4:3

Plastic zippers and hollow-tube zippers on yacht sunshades and cockpit covers

ImageBack or chest zipper on a wetsuitmr-scene-wetsuit · 4:3

Spiral zippers used for wetsuit back zips or chest zips

ImageKayak waterproof bags and dry bagsmr-scene-drybag · 4:3

Track-type waterproof zippers used on waterproof bags and kayak dry bags

Application	Common sizes	Selection notes	Recommended KCC products
Sunshade and cockpit cover main zipper	#10	Large wind-loaded area under high load: use the CF10 spiral zipper, lateral strength per inch 1000 N (Class E+). Open end, often with a double-sided slider for operation from inside and outside	CF10
Canvas side panels, door flaps	#8 / #10	Lower-load areas; plastic teeth resist salt spray and UV	VF8, VF10
Quick-release deck canvas	Per track design	Flexible canvas repeatedly fitted to and removed from a rigid hull	Hollow-tube zipper
Canvas pockets, storage bags	#5 / #8	Water-repellent tape to keep water from seeping in at the seams	VF5, Plastic zipper (waterproof tape)
Seat cushions, cockpit upholstery	#5 / #8	Polyester teeth, UV-resistant	CF5, CF8
Wetsuit back zip	#8 / #10	Long zipper from the lower back to the neck; easy on and off	CF8, CF10
Wetsuit chest zip	#5 / #8	Short zipper of about 29 cm; more freedom of movement for paddling	CF5, CF8
Windsurfing, kayaking and SUP apparel	#5 / #8	Diagonal shoulder or back entry; must be weather-resistant	CF5, Spiral zipper (standard waterproof tape)
Waterproof bags, kayak dry bags	#3 / #7	From powerful water jets to brief immersion (IPX6–IPX7; theoretical rating, testing in progress)	Track-type waterproof zipper
Life jacket front zipper	#5	Large slider, operable one-handed even with gloves on	CF5, VF5, Sliders & pullers

KCC standard products currently go up to #10. The extra-large #12 and #15 sizes often used for canvas on larger vessels are a special specification; please enquire.

Waterproofing levels

Choosing a water-repellent or waterproof zipper by application

Level 1 · Water-repellent

Canvas, sunshades, general water-sports apparel

The tape has a water-repellent finish, so droplets roll off it and the zipper seam does not become a leak point. A water-repellent zipper roughly corresponds to IPX3–IPX4 (theoretical rating; KCC testing in progress).

KCC: Spiral zipper (standard waterproof tape); Plastic zipper (waterproof tape)

Level 2 · Waterproof

Waterproof bags, kayak dry bags

IPX6 means protection against powerful water jets; IPX7 means no water ingress after immersion at 1 m for 30 minutes. Level 2 consists mainly of waterproof zippers with a one-piece, press-sealed track and no individual teeth. By its construction, the KCC track-type waterproof zipper corresponds to IPX6–IPX7 (theoretical rating; testing in progress).

KCC: Track-type waterproof zipper

Recommended KCC products

Specifications of KCC hollow-tube, spiral, plastic and track-type waterproof zippers

ImageHollow-tube zipper tape and rigid tubemr-p-tube · 4:3

Industrial Zipper · Specialty product

KCC hollow-tube zipper

The tape of the KCC hollow-tube zipper has a tube channel, and the standard teeth are polyester. With a rigid tube inserted, the zipper seats in a hull track or joins to rigid structures; with a flexible tube, the whole zipper can bend to follow curved surfaces. The KCC hollow-tube zipper is used in quick-release yacht canvas systems.

Rigid tube: Seats in the track groove, joining flexible canvas to the hull
Flexible tube: Bends to follow curved surfaces during installation

SunshadesCockpit coversDeck canvas

Industrial Zipper category page

ImageClose-up of CF10 sewn onto a sunshademr-p-cf · 4:3

Spiral Zipper series · Standard product

KCC CF series spiral zipper

KCC CF series spiral zippers have polyester teeth that do not rust, and the tape is soft and conforms to the fabric. CF10 has a lateral strength per inch of 1000 N (Class E+) and is used for main zippers on sunshades and cockpit covers with large wind-loaded areas. CF5 and CF8 are used on wetsuits, windsurfing apparel and cockpit upholstery, and can be paired with waterproof tape.

Sizes: CF5, CF8, CF10
Lateral strength per inch: CF10 1000 N · CF8 900 N · CF5 663 N (all Class E+)
Tape: Standard tape, waterproof tape

Sunshade main zippersWetsuitsCockpit upholstery

CF10 CF8 CF5

ImagePlastic zippers VF8 and VF10 side by sidemr-p-vf · 4:3

Plastic Zipper series · Standard product

KCC VF series plastic zipper

KCC VF series plastic zippers have teeth injection-molded from POM resin, and the teeth do not rust. The VF series suits lower-load areas such as canvas side panels, door flaps and storage bags, can be paired with waterproof tape and comes in a range of end types.

Sizes: VF5, VF8, VF10
Lateral strength per inch: VF10 561 N · VF8 510 N (all Class E+)
End types: Close end, open end, 2-way open end, double bottom stop, double top stop

Canvas side panelsDoor flapsStorage bags

VF10 VF8

ImageSealing cross-section of a track-type waterproof zippermr-p-track · 4:3

Specialty product

KCC track-type waterproof zipper

The KCC track-type waterproof zipper seals by pressing together a one-piece TPU, EVA or PVC track and has no individual teeth. Once closed, the track forms a watertight chamber, which suits waterproof bags and kayak dry bags. By construction, the waterproofing level corresponds to IPX6–IPX7 (theoretical rating; testing in progress). The KCC product site currently has no individual page for this product; please enquire for specifications.

Sizes: #3 close end; #7 close end, open end
Material: TPU / EVA / PVC

Waterproof bagsKayak dry bagsExpedition gear

Enquire about track-type waterproof zipper specifications

Lateral strength per inch is the crosswise force a closed zipper withstands per inch of width. Values from the KCC product site, converted at 1 kgf ≈ 10 N for convenience. Strength class per EN 16732; “+” means above that class.

Validation tests

Common validation tests and industry reference values for marine zippers

The table lists common validation tests for marine zippers with common industry reference conditions; these are not KCC test results. Actual requirements are set by the specifications of the brand, shipyard or certification body.

Test	Standard or method	Typical requirement	Notes
Salt spray corrosion	ISO 9227	≥ 96 h	Typically 48 h for general apparel; a higher level is recommended for marine use
Artificial weathering	ISO 4892-2, 500 hours	Tape strength retention ≥ 90%	Assesses the weathering resistance of the tape and resin teeth
Waterproofing level	IEC 60529 (IPX)	IPX4–IPX7 depending on application	Waterproof bags often require IPX6–IPX7
Lateral strength	ASTM D2061	#10 ≥ 1000 N	Industry reference value for marine canvas main zippers
Life jacket materials and components	ISO 12402 series	Per certification body requirements	Zipper tape, teeth and slider fall within the scope of component testing
Life-saving equipment on merchant ships	SOLAS Convention, EU MED	Type approval	Certified as complete equipment; all trims and components are in scope
Low-temperature operation	Standards for immersion protection and life-saving equipment	Opens and closes normally at low temperatures	Tell us the target certification early in development

Some marine hardware (such as hull fasteners or electrical connectors that stay fixed or submerged for long periods) requires salt spray testing of 500 hours or more. Zippers are opened and closed frequently and are usually rinsed with fresh water, so that level is not generally used as an acceptance criterion for them.

Before you start

Operating conditions, drawings and quality documents to prepare before evaluating marine zippers

Operating environment

Tell us whether the zipper is for canvas, apparel or a waterproof bag, and how often it is exposed to sun, immersion and washing, so the tape treatment and waterproofing level can be determined.

Drawings and specifications

Provide zipper length, size, end type and slider requirements. For hollow-tube zippers, include drawings of the hull track groove and tube.

KCC company and quality systems

KCC (KEEN CHING) ZIPPER was founded in Taiwan in 1976 and is headquartered in Taipei. KCC operates zipper plants in Tongxiang, Zhejiang, China and Ho Chi Minh City, Vietnam, and has sales offices in locations including Europe, India and Hong Kong.

KCC's production system is certified to ISO 9001 (quality management), ISO 14001 (environmental management), ISO 45001 (occupational health and safety management) and the Global Recycled Standard (GRS), among other system certifications, and undergoes annual Worldly and BSCI assessments. KCC products also hold OEKO-TEX Standard 100 Class I product certification. KCC plants have in-house salt spray chambers, UV resistance testers and xenon-arc weathering testers. The KCC plant in Vietnam is close to Southeast Asia's water-sports apparel manufacturing industry.

FAQ

Questions from shipyards, canvas makers and brands

Why are metal zippers not recommended for marine use?

Metal zippers are not recommended because a high-salt environment corrodes metal sliders and teeth quickly; in severe cases the whole zipper seizes and can no longer open or close. Marine canvas generally uses plastic zippers or spiral zippers instead, and we recommend ISO 9227 salt spray of 96 hours or more as an acceptance reference.

Do sunshade sliders need a locking function?

Sunshade sliders usually do not need a locking function. Marine sunshades and cockpit covers often use non-locking sliders by design, so the canvas can be pulled open by hand in an emergency, and conventionally use double-sided sliders so the zipper can be operated from inside or outside the cabin. When selecting, please describe how the zipper will be operated and any safety requirements.

Should a wetsuit use a back zip or a chest zip?

Entry-level and rental wetsuits mostly use a back zip, and performance wetsuits mostly use a chest zip. A back zip runs from the lower back to the neck and makes the suit easy to get on and off. A chest zip is a short horizontal zipper of about 29 cm with no zipper on the back; a chest zip allows freer paddling and lets in less water. There are also zipperless designs that rely on high-stretch fabric to pull on, but zipperless suits take more effort to get in and out of.

Are there certification requirements for life jacket zippers?

Yes. Life jackets obtain type approval, such as ISO 12402 or SOLAS / MED, as a complete product, and the zipper falls within the scope of materials and component testing; certification cycles are also longer. Please tell us your target markets and certifications early in development so sample submission and testing can be planned.

Should the main sunshade zipper be a spiral zipper or a plastic zipper?

For a main zipper with a large wind-loaded area and high loads, we recommend the KCC CF10 spiral zipper, with a lateral strength per inch of 1000 N (Class E+), which meets the common industry reference value of ≥ 1000 N for marine canvas main zippers. For lower-load areas such as canvas side panels, door flaps and storage bags, a plastic zipper such as the KCC VF10 can be used. Unlike metal teeth, the teeth of both spiral and plastic zippers do not corrode and seize in salt spray.

Tell us about your vessel and operating environment

Share the application, zipper length and size, and waterproofing needs, plus track drawings for hollow-tube zippers. KCC will support selection, sampling and testing.

Contact the KCC sales team

This page is a general selection reference. Test conditions and requirements are common industry reference values; actual standards are set by the specifications of the brand, shipyard and certification body. KCC product specifications are subject to the specification sheet and sample test results.

At sea, zippers have to withstandsalt spray, strong sun and high winds