Includes 7-pc. 1/4 in. drive 6-point u-joint sockets: 1/4, 5/16, 11/32, 3/8, 7/16, 1/2, 9/16 in.; Socket rail Combines a shallow 6-point socket and compact universal joint fits into extremely limited spaces when other tools can't fit. Socket geometry is designed to apply force to flat sides of fasteners and not the corners, preventing round-off Extra-large die-stamped size markings are easy to read and can’t wear off Polished, chrome-plated finish easily wipes clean and is highly resistant to corrosion Four detent grooves provide a secure connection with the drive tool Beveled inner rim of the socket opening helps guide it smoothly onto fasteners Twist-to-lock socket rail organizes and securely holds sockets in place, both for in your toolbox and on the go