"Galvanized Anchor Shackl, 1/4 150;In. Pin Diameter" by Peerless
Click Image to Enlarge:
"Quick, easy approach for connecting different styles of accessories. Use with chain of equal or lower working load limit. Each with screw pins. 3/16 in. bow diameter1/4 in. pin diameter7/8 in. inside length3/8 in. inside width21/32 in. bow width1500 lb. safe working load"