Generic Plastic Black 0.5" Inside Diameter Oval Ring Lobster Clasp Swing Claw Swivel for Strap Pack of 20 Inside swivel tail D ring diameter:0.5". Lobster clasp total Length:1.65". Snap opening mouth maximum size about:0.15". Lobster all kinds of purse or bag strap connector. Full 360 degree swivel eye helps prevent tangles.