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Each ring is approximately 7mm outside diameter and 4mm inside diameter
Rubber hinged rings that provide flexible tension for a secure and comfortable fit
Simply slip a frame grip up each bow over the hinges: The resulting flexible tension will give a tight, comfortable fit for most glasses
Measure your bows to make sure that a 4mm ring will fit
Made in the USA

Eyeglass Frame Grips--Hinge Tighteners - Rubber hinged rings that provide flexible tension for a secure and comfortable fit. Simply slip a frame grip up each bow over the hinges. The resulting flexible tension will give a tight, comfortable fit. Pins and screws in these hinges cannot become loose or fall out. 24 Pairs of rings in each package - 48 total rings. Each ring is approximately 4mm inside diameter. Please measure your bows to make sure that these will fit.