Klean Kanteen Cafe Cap/Black/Bpa Free/Dishwasher safe (Set of 2) Made from BPA-free polypropylene and food-grade silicone, this cap is safe for use with acidic or hot beverages Large silicone valve ensures flow when you need it and a robust seal when you don't Minimal parts make this cap both durable and easy to keep clean Intuitive threaded system makes disassembly easy Top-rack dishwasher safe Pairs with TK Closure internal thread design to increase thermal performance