2Pcs Silicone Boot Sleeve for Stanley Cup Accessories, Protective Water Bottle Bottom Cover for Stanley 40 oz Tumbler with Handle

I have several hydroflasks which I have a a sleeve that came with it but it can rip and tear over time. This is a great replacement that not only fits well but it slightly thicker than the name brand which gives it more durability and also more cushion. Only drawback is the slightly thicker rubber makes it fit a little tighter in certain cup holders. Otherwise a great product.