Did you know that THE NATIONAL FIRE PROTECTION AGENCY sets standards for the installation and maintenance of Fire-Rated Door Assemblies. According to NFPA 80, section 6.4.3.4, steel shims are the ONLY acceptable shim to be used when shimming Fire-rated Door Assemblies. MOST commercial installers do not know of this requirement. Our 16 gauge peel and stick Ready Shim works perfect for Fire Doors and satisfies NFPA 80. These READY SHIMS are REMOVABLE, RESTICKABLE and STACKABLE.Place them behind the hinge to push door towards the strike or to pull away from strike.You'll Shim doors in less than a minute. They work like a charm !! DOOR GAP GAUGE INCLUDED !! The Door Gap Gauge tool is a sure way for Contractors to check Fire Door Clearance Requirements before inspection. It's more accurate than a tape measure and is compact and very easy to use. 1/16th, 1/8th, 3/8th, 1/4th, 3/16th, 3/4th inch readings. NFPA 80 requires the clearance between the door and frame and meeting edges of doors swinging in pairs to be 1/8" (+/- 1/16") for Steel Doors and not to exceed 1/8" for Wood Doors. The clearance under the bottom of a door and noncombustible surface where no sill exists shall be a maximum of 3/4" and shall be a maximum of 3/8" under the bottom of a door with raised non combustible sill. It's simple to use : The clearance should be measured from the pull face of doors. Just locate the dimension portion of the gauge needed to measure your gap. Insert the gauge between the door and frame or at the door bottom. QUANTITY = 50 SHIMS PER PACK