Facom Angled Open-Socket 10pc Wrench Set (75 series) - fractional sizes include........5/16 - 3/8 - 7/16 - 1/2 - 9/16 - 5/8 - 11/16 - 3/4 - 13/16 - 7/8 .
Ddeep recess at one end and open end socket at the other fit over protruding studs (6-point, both ends). The angle and through hole design accommodates threaded rods or a bar for extra leverage without affecting wrench strength. This is one of my favorite Facom products for field installations (cabinets, shelving, garage door track, etc).