Replacement Spark plug cap kit to suit 3/4" Hex Plugs. (ie NGK BPMR6A or Bosch R-10 etc, 3/4 hex, taper seat plugs)
Made by RCXEL, but suitable for many brands of ignition.
3/4" converts to 19mm (hexsize).
Stainless steel body
Includes everything in the photo.