Helps protect your wrist from irritation / contact dermatitis / allergy due to sweat & watch band material.* BANDLINERS add years of wearable life to most leather, rubber, metal, and nylon watch bands, including Apple Watch, other major brand smart watches, and any other buckle & strap style watch band. NOT COMPATIBLE WITH SILICONE WATCH BANDS. Designed to completely block sweat and skin oils from making contact with your watch bands, significantly extending wearable lifespan. Replaceable, ultra-thin microfiber BANDLINERS are a subtle addition to your watch band that provide both hypoallergenic* benefits–in addition to significantly added comfort. Our unique high-tack adhesive stays firmly attached while remaining removable from most leather, rubber, metal, and nylon bands. Customers should note that BANDLINERS will not currently adhere to certain bands made from silicone & urethane. Customers should use discretion with use on ALL leather watch straps, especially unlined or sueded leather straps, as the BANDLINERS may adhere more aggressively to these materials. Bandliners are intended to extend the lifespan of watch straps by preventing contact with sweat and skin, and they are not intended to preserve the integrity of the surface upon which they're applied–removability will vary. Questions? Feel free to post; we're happy to respond! *These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.