Designed to fit in limited space on many water-cooled 2-stroke enginesRatchet mechanism works one way, turn over to reverse Fits standard 13/16" plugs Kit includes Ratcheting Spark Plug Wrench (part no. 678147) and 13/16" Extension Socket (part no. 142225) 13/16" Extension Socket allows the Ratcheting Spark Plug Wrench to be used on recent models where the water neck prevents the use of the Ratchet Plug Wrench alone