Built to handle the tough jobs with ease. Hex bolster reinforces shank for hard use and allows wrench assisted turning. 5/16-Inch keystone-tip screwdriver. Klein offers a lifetime warranty on material defects and workmanship for the normal life of the product. The product is 5/16" x 6", Cushion Grip, Screwdriver With Keystone Tip, Round Shank.. Easy to use. The product is manufactured in China.