For spiral zippers, we also supply seawater-resistant plastic sliders. These sliders are particularly suitable for zippers that are permanently exposed to salt water, for example on ships and boats or facilities close to the sea. Most of these sliders consist of the plastic PolyOxyMethylene (POM), also known as Polyacetal or the DuPont brand Delrin®. Only the nonlock-sliders for 10 mm chain width are made of fibreglass reinforced plastic (FRP) with 50% nylon (polyamide 6.6) and 50% glass fibers. Due to this material composition, these sliders resist greater forces and deform less than sliders made of POM.

The polyester plastic of spiral zippers is already seawater resistant. The sliders are produced using injection moulding. For injection molding, the above plastics are better suited than polyester.

The plastic sliders up to 5 mm chain width are only free-running, which means non-lock. From 6 mm chain width there are also automatically locking sliders (automatic sliders, autolock). Their locking thorn is made of brass and the spring is made of stainless steel.