The clutch on a drill/driver is similar to the one in your car—it engages and disengages the drivetrain. This feature allows you to control the amount of torque applied to a screw or fastener, preventing overdri.
[pdf] As a kind of friction clutch that uses compressed air as manipulating power source, pneumatic-tyred clutch is widely used in such equipment as oil drilling rig and workover rig, and is also an important part of the drive systems of oil drilling rig and workover rig.
[pdf] Featuring all metal gears for added durability, this 18-Volt Lithium-Ion Cordless 2-Speed 1/2 in. Compact Drill/Driver Kit is the perfect addition to your toolkit. Each kit includes Drill/Driver, 2 Batteries, Charger, and Tool Bag.
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