322, Zinc, Adjustable Door Guide, Designed For Single Sliding Or BiParting Metal Or Wood Doors, Intended To Take Abuse From Trucks, Tractors Farm Machinery When Used Around Factory Farm Buildings, Smooth Ramp On Each Side Of The Guide Prevents Cutting Tractor Or Truck Tires, Mounts On Concrete Floors With Lag Screws Shields Or On 6 x 6 Post, 12 Rod Or Bolt Inserted Through Hole In Each Side Will Serve As A Center Stop For BiParting Doors, Meets ANSIBHMA, 15614 Manufactured From Hot Rolled Steel, Bulk