Stanley FBB Series 06-8278 Hinge, 4 in H Frame Leaf, Steel, Satin Brass, Full-Mortise

These tough, hardened, chrome alloy, vertical thrust ball-bearing assemblies support the vertical load of the door, as the pin bearing on the inside of the hinge knuckles supports the lateral load of the door. FBB hinges are approved for use on fire-rated doors since they contain anti-friction bearings, a requirement for fire-rated and self-closing doors.