Silicone. Double smart wallet with 3M adhesive tape at the back. Use to hold up to four credit cards, ID, hotel cards or debit cards . (2 in each slot). Will not demagnetize your cards. Apply to the back of your phone or case. Fits most flat backed Smartphones. Use this wallet so you don't have to carry your entire wallet. 3 9/10" Lx 2 1/4" W.
