The Hydro Flask Stainless Steel Cap is perfect for those who want their liquids to never come in contact with plastics,
The top is constructed of polypropylene PP#5, while the inner treads that touch the liquid are 18/8 stainless steel,
As with all Hydro Flask products, this cap is BPA and toxin free,
Fits on Hydro Flask Standard Mouth flasks, including the 12 oz and 21 oz flasks,
Features: Top: Polypropylene PP#5 Inner Treading: 18/8 stainless steel BPA free Toxin free Compatible with Hydro Flask Standard Mouth flasks, including the 12 oz and 21 oz