11 Pcs Impact Screwdriver Set
To use simply tap tail of handle with hammer, ture head to tighten and loosen screw.
Set Includes:
1 Pc 1/2" Dr. Impact driver with a bit holder(1/2"x8mm hexagon).
6 Pcs 36mm Length Bits: PH2, PH3, PH4, Slotted 6mm, Slotted 8mm, Slotted10mm.
4 Pcs 80mm Length Bits: PH2, PH3, Slotted 8mm, Slotted 10mm.
Material:
Handle made from chromium vanadium steel.
Bits made from S2 steel.
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An impact driver is a tool that delivers a strong, sudden rotational and downward force. In conjunction with toughened screwdriver bits and socket sets, they are often used by mechanics to loosen larger screws (bolts) and nuts that are corrosively "frozen" or over-torqued. The direction can also be reversed for situations where screws have to be tightened with torque greater than a screwdriver can reasonably provide.
Manual impact drivers consist of a heavy outer sleeve that surrounds an inner core that is splined to it. The spline is curved so that when the user strikes the outer sleeve with a hammer, its downward force works on the spline to produce turning force on the core and any socket or work bit attached to it. The tool translates the heavy rotational inertia of the sleeve to the lighter core to generate large amounts of torque. At the same time, the striking blow from the hammer forces the impact driver down into the screw reducing or eliminating cam out. This attribute is most beneficial for Philips screws which normally cam out as part of their design. It is less beneficial for flat head, also known as common, screws and is not beneficial at all for most other types.
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