ACCEL, U-GROOVE SPARK PLUGS, ONE RANGE COLDER

Accel, U-groove spark plugs, one range colder

H-D #3-4. 14mm threaded, short reach. Used with 21mm spark plug socket. Used in high performance or hard ridden engines in which standard heat range plugs become overheated.

Fits: > 48-74 B.T.(NU)