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A champion of adjustability, Croakies Endless Cord with Tite End grips offers the most flexibility when shortening or lengthening the cord.. . . Tite End grips provides best fit on medium-width temples. Two molded beads attach to Terra Cord for pull-apart adjustability. Endless range of cord adjustments: Slide beads apart or together for shorter or longer cord lengths: 18 to 33 in. (45.72 to 83.82 cm). 3.2 mm (diameter) woven climbing rope for durability over years of use. Nonslip Tite End grips made from UV-resistant plastic for durability and a secure hold. Ends can be positioned anywhere along the temple keeping the ear bow free. Moisten temples of glasses to attach or remove the ends. Washable and colorfast.