Dawson Sockets - The Original Patented British Design - Made In Sheffield England to the highest quality and specification. Dawson Socket specification - 3/4" (19mm) Channel Unistrut Socket is designed for use with all 3-1/4", 2-7/16", and 1-5/8" channel, allowing for easy tightening and loosening of ½” bolts with ¾” heads that can’t be accessed with a traditional ¾” socket head.
eBay