NUOLUX 5 Colors Eyeglass Strap,Eyewear Retainers for Kids Fit for the children's Eyeglass! Adult's will a little tight !!!! NOTE1:The anti-slip silicone strap is more suitable for Acetate Glasses Legs, NOT for Thin Metal Glasses Legs NOTE2:It is applicable to the eyeglasses legs' tail width up to 9mm. Hole size for glasses legs: 0.9cm*0.2cm. Total length: 22cm. (Elastic design allows you to stretch the strap up to 50cm).