How does it compare with a pistol-grip impact wrench?

It reaches places a pistol-grip tool cannot because the head is only 2.8 inches deep. You often skip the socket extensions a pistol-grip impact needs in tight spots. It gives up some peak torque compared with full-size 18V impacts.

What does Auto Shut-off Mode do?

In forward, Mode 4 stops applying torque above about 15 ft-lbs so you do not over-tighten small bolts. In reverse, Bolt Removal Mode slows the RPM once the bolt breaks loose so the fastener does not spin off.

Does it come with a battery and charger?

The 2564-20 is the bare tool. It takes any M12 REDLITHIUM battery pack, which is sold separately and shared with other M12 tools.

What size sockets does it take?

It has a 3/8-inch square drive with a friction ring, so it takes standard 3/8-inch impact sockets. The ring holds the socket without a pin detent.

Is it strong enough for lug nuts?

It can loosen many passenger-car lug nuts, but 220 ft-lbs is below what full-size impacts deliver. For heavily torqued or rusted fasteners, use a breaker bar first.

Mechanics and serious DIYers who already own M12 batteries and need access in engine bays, brakes and tight chassis areas. Casual users may find a larger impact or a ratchet more useful.