• WHITE USA- 3/8 JACOBS CHUCK AND KEY WITH 7/16 HEX SHANK DRIVER. Its 1/2"-20 mount with 1/4"-20 left hand cap screw to prevent chuck reversal. Great tool for Lineman.Condition is New. Part# is SHJAC1412. Shipped with USPS Priority Mail. Ships same business day if ordered before noon Mon.-Fri.