A&L Shielding’s Bullet Resistant Hollow Metal Window Frames are available for UL 752 at Level 1, 2, 3 & 6. Our standard frames are primed 16 gage cold rolled steel, with 2” faces, head & sill, masonry double rabbet profile with anchors and jamb depth as required to meet your wall requirements. We also offer 12 or 14 gage frames when needed.