Socket

A socket is an interchangeable, cup-shaped sleeve that fits over a bolt head or nut, connecting it to a ratchet, breaker bar, or torque wrench. Sockets are the interchangeable tips of the socket wrench system — one handle drives dozens of sizes.

How it works

The socket’s interior is hexagonal (6-point), twelve-point (12-point), or Torx-shaped to match the fastener. The exterior has a square hole that fits onto the square drive of a ratchet or extension bar. You select the socket that matches your fastener, snap it onto the drive, and turn the handle. The enclosed design grips all faces of the fastener simultaneously, allowing higher torque without slipping.

Drive sizes

Socket wrenches use standardised square drive sizes:

• 1/4-inch drive: For small fasteners — electronics, small bolts, precision work.
• 3/8-inch drive: The most versatile size — general automotive and home repair.
• 1/2-inch drive: For larger, higher-torque fasteners — wheel nuts, suspension bolts, structural work.
• 3/4-inch and 1-inch drive: For heavy-duty industrial and commercial applications.

Socket types

• Standard (shallow) socket: Fits bolts that protrude above the nut. The most common type.
• Deep socket: Has a longer body, allowing it to reach recessed bolts and threaded studs that a shallow socket cannot clear.
• Universal joint (U-joint): A swivelling adapter that lets the socket reach fasteners at an angle.
• Socket set: A collection of sockets, extensions, and adapters in a case, covering a range of sizes and drive types.