Rectangular arc chucks are inserted into the end of a stud welding gun to hold the rectangular stud before and during application. This chuck can only be used with rectangular studs. Rectangular studs are also called Christmas Tree Studs or InsulTwist Studs. 8 Sizes Available:1/4", 3/8" and 5/8" Size Hanlon Stud Welding Nelson Proweld Truweld Image Midwest Fasteners Erico/KSM 1/8 x 1/4 ACR1814 500005118 CR-CA, CR CA C1225 1/8 x 5/8 ACR1858 500005014 CR-CC, CR CC C1262 102-0102-12 033-791 1/8 x 3/8 ACR1838 500005003 CR-CB, CR CB C1237 102-0102-11 033-790 1/8 x 3/4 ACR1834 500005021 CR-CG 1/8 x 7/8 ACR1878 500005005 CR-CH 1/8 x 1 ACR181 500005006 CR-CE 1/4 x 3/4 ACR1434 50000501 CR-CF 1/4 x 1-1/4 ACR14114 CR-CJ
