A waterproof zipper is a specialized type of zipper that is designed to prevent water from penetrating through the teeth or coils of the zipper. This type of zipper is commonly used in outdoor clothing and gear such as rain jackets, backpacks, and dry bags.

Waterproof zippers are typically made with a rubberized coating or a waterproof membrane that seals the teeth or coils of the zipper, preventing water from seeping through. Some types of waterproof zippers are also designed with a locking mechanism that creates an airtight seal when the zipper is closed, further increasing their water-resistance.

Although waterproof zippers offer superior protection against water compared to regular zippers, they may be more expensive and require more care and maintenance to keep them functioning properly. Additionally, they may be more difficult to repair if they become damaged.