The spark plug socket can be used with a reversible ratchet (3/8") or a combination spanner (SW 17 mm). Thanks to its extra thin-walled design, spark plugs can be installed even in narrow spark plug shafts. The spark plug is held in place during installation by a rubber insert inside the socket. Material: hardened steel Number of edges 12 Article type Version Spark plugs Outer diameter 26.5 mm Area of use Spark plug wrench Main colour black Length 50.0 mm Spanner size 21 mm