Metal framing screws are used when attaching the metal studs to one another during the framing process. Often these screws are referred to as zip screws.
ACR stands for anti-cam-out recess. There are ribs on the driver bit that engage the patented recess to reduce stripping, provide increased torque, enhance off-angle drivability, and offer a stick fit that makes screw driving easier. Phillips II Plus Screws can be driven with a standard square bit, a Phillips Bit, and a Phillips II Plus Bit. For the features of the patented ACR system, we recommend the Phillips II Plus Bit that is included.