The Champion 237 RB77CC Industrial Spark Plugs are a set of 4 high-quality spark plugs designed for industrial use. With a thread diameter of 18mm, these spark plugs are made of durable copper material and are suitable for a variety of ignition systems. The OE/OEM part number and manufacturer part number are 237 RB77CC, ensuring compatibility and reliability for your vehicle or equipment. Trust in the Champion brand to provide reliable and efficient spark plug performance for your industrial needs.