More descriptively, a Screw Pin Anchor Shackle, an attachment device used in stage rigging.
http://www.slings.com/servlet/the-8464/Crosby-G209-4.75t-Screw/Detail
http://www.all-lifts.com/shackles1.htm
Sized by the diameter of the thinnest part, at the bell, ranges from 3/16" (WLL: 1/3 ton) to 2 1/2" (WLL: 55 tons). See also Crosby Forged Shackles - BC Wire Rope&Rigging.
http://www.slings.com/servlet/the-8464/Crosby-G209-4.75t-Screw/Detail
Sized by the diameter of the thinnest part, at the bell, ranges from 3/16" (WLL: 1/3 ton) to 2 1/2" (WLL: 55 tons). See also Crosby Forged Shackles - BC Wire Rope&Rigging.
