This replacement kit includes one bottle stopper and one O-ring, designed for a perfect fit with WaterH Boost smart water bottles. Crafted from high-quality, BPA-free silicone, these parts are soft, flexible, and durable, providing a reliable leak-proof seal. Both pieces are dishwasher-safe for easy cleaning, or can be hand washed with warm water and mild soap. Compatible with 24oz and 32oz WaterH Boost bottles. Not for use with other brands or sizes—please confirm your bottle model before ordering.