Tianbang Black 0.55" Inside Diameter D Ring Lobster Clasp Claw Swivel for Strap Pack of 20 Swivel tail D ring inside diameter:0.55". Lobster clasp total Length:1.55". Snap opening mouth maximum size about:0.21". Lobster all kinds of purse or bag strap connector. Full 360 degree swivel eye helps prevent tangles.