Qty. (5) 0.625″ ID rubber grommets. I.D. of grommet is 5/8″, hole in panel should be 7/8″, O.D. of grommet is 1-1/8″. Maximum panel thickness is 1/16″. Overall thickness of grommet is 5/16″. These are designed to protect wires, hoses, tubing and/or cable when going through a firewall or bulkhead in a vehicle or piece of equipment. Original application Military Trucks such as the M35, M939, M151, and others. DPEquipment R2C5