Sew On Rings, 50 Pack UV Stable will not become brittle and break from sun exposure. Will not melt even if touched by a hot iron. Suitable for fabric shades, tie backs, etc. High abrasion resistance. Sometimes referred to as the bone ring. Can be used with 1.4mm and 1.8mm cord Clear Sew On Rings, 50 Pack. UV Stable will not become brittle and break from sun exposure. Sometimes referred to as the bone ring. Will not melt even if touched by a hot iron. High abrasion resistance. Suitable for fabric shades, tie backs, etc. Diameter: 3/8 inches Inside Diameter - 5/ 8 inches Outside Diameter