• Thin Wall 3/8" Drive/17mm Shaft Spark Plug Socket 6-Piece Set
• Made in Japan of the highest quality materials
• Includes: 16mm Socket(5/8"), 18mm Socket, 21mm Socket(13/16"), Short Extension, Long Extension, Metal Case
• Ball Bearing Detent Retainer System Prevents Broken Spark Plug Ceramic
• Ultra Thin Spark Plug Socket Set with Metal Case

The socket sizes are:
The one marked "10" is a 16mm or 5/8"
The one marked "12" is an 18mm
The one marked "14" is a 21mm or 13/16"

The secret is the small retaining ball that grips the spark plug. This system eliminates magnets or rubber grips and allows the plug to "float" in the socket eliminating accidental cracking of the porcelain. The reduced shank also makes this the ideal socket for hard to reach areas such as Porsche 911, and VW rear plugs as well as many other applications.
This item will fit the following machines and other metric machines:
Kawasaki
Honda
Yamaha
Buell
Norton
Metro
Triumph
Thunderbird
Porsche
Volkswagen
BSA
Moto Guzzi