Product: Ball bearing hinge with Non-Removable Pin. Series: FBB. Type: Heavy Weight Ball Bearing (wood or hollow metal). Application: wood or metal doors; heavy weight doors of high frequency. Knuckle: 5. Handing: Non-handed. Size: 4.5" x 4.5". Weight: Heavy. Finish: US26D Satin Chrome. The FBB Series hinges are ball bearing hinges that conform to ANSI A156.1. These tough, hardened, chrome alloy, vertical thrust ball-bearing assemblies support the vertical load on 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. For use on heavy doors or doors where high frequency is expected as entrance doors to office buildings, stores, public buildings and corridor entrance doors to offices. All hinges have template screw hole location for use on either wood or hollow metal doors and frames. Equipped with four Stanley permanently lubricated non-detachable ball bearings. Pins in non-ferrous hinges are stainless steel. Reversible flush tips and pins.