CHANNELLOCK Mechanics Tool Sets come equipped with a full selection of the most commonly used sockets, wrenches, ratchets and more all contained within a durable molded case for easy and secure storage. Deep and standard sockets feature DYNA DRIVE technology which offers 20% more torque, eliminates slippage, and prevents damage to fasteners. The 39053 171 piece CHANNELLOCK Mechanics Tool Set includes: 3 drive sizes (1/4, 3/8, 1/2 inch), Combination Wrenches, Quick Release Oval Head Ratchets, Extensions, Deep Well, Standard, and Spark Plug sockets, SAE and Metric 8pc Hex Key Set, high torque Magnetic bit Nut Driver with 4 bit sets, and a Magnetic Parts Tray. The 39053 171pc CHANNELLOCK Mechanics Tool Set is made to A.N.S.I. standards in Taiwan.