9.5 mm or 8 mm
Straight Spark Plug Boot or 90 degree Spark Plug Boot
 
9.5mm comes in Red, Black, or Blue
8mm comes in Black only 
 
Call for availability.
 
9.5mm Straight: D-3201
9.5mm 90 degree: D-3202
8mm Straight: D-3203
8 mm 90 degree: D-3204