Knocked-down (KD) hollow metal frames are shipped un-assembled with hardware and anchors designed to secure the frame when assembled in a rough opening.
Knocked-down drywall frames have a corner gusset and interlocking slots and tabs for field assembly. A #8 pan head screw should be installed in the returns on each end of the head. The screws engage the mating jamb, closes the miter, and improve squareness when properly adjusted.
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