About HEYSKAY flask silicone boot-BPA free soft silicone material-Fits Hydro flask perfectly and the other brands which diameter is the same as Hydro flask like as Simple, Mira, Yeti (note: a bit tight for Yeti but ok to put on) Bright up your Hydro flask look-No noise any more when landing your flask on desk and protect your flask bottom from dama..

HEYSKAY protective silicone boot was designed for 24oz 32oz 40oz stainless steel Owala Twist,FreeSip or Flip water bottles; Also perfect for Owala 40oz tumblers and Stanley Quencher(30/40oz) H2.0 and Stanley lceFlow (20/30 oz) Tumblers. It also fits other brand water bottle which bottom diameter is from 2.85inch to 3.65inch. NOT intended for Owala ..