Heavy-duty jobs call for heavy duty tools. The STEELMAN PRO 79376 3/4-Inch Drive x 4-Inch Long Impact Extension Bar is made to give you the reach you need on those tough jobs that demand the most of you and your tools. Ideal for use in performing maintenance, repairs and service on large trucks and trailers, farming equipment and tractors, oilfield and construction equipment, mass transit vehicles, and similar projects, this durable tool is forged from resilient chromoly steel to endure a lifetime of long use. This 4-inch extension gives you just that little bit of extra reach you need to reach recessed or hard-to-access fasteners. Made to be compatible with any heavy-duty 3/4-inch drive ratchet, torque wrench, adapter, and socket, this tool is here for the long haul with a rust and corrosion resistant black phosphate protective coating. A spring loaded detent ball on the male end of the extension secures attached sockets and a ball detent recess on the female end holds the extension securely to a ratchet or other drive tool. Designed to meet or exceed ASME tool standards this extension is covered by a limited lifetime guarantee.