Home Sewing Depot 1000 - 3/8 Inch White Sew on Uv Rings for Shades 3/8" White Sew On Rings, 1000 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