Wiring Grommets | Firehose | Isolation | Door Bellows Ritus manufactures a variety of wiring harness grommets used to route large wiring bundles through the cavity of a vehicle. Some grommets are molded entirely from rubber while others are a hybrid of rubber and plastic materials. We are capable of manufacturing a range of sizes from very large to small. Steele Rubber Products - Firewall Grommets Firewall grommets carefully sized to protect hoses and prevent leaks. Made from quality rubber products. Grommet set, firewall, intended for spark and choke rods, fuel line, oil gauge line and radiator brace rods. Grommet, main wiring harness and misc. wires through firewall (main cable and up to eight (8) other wires, tubes or cables).