472-12STD Harley JD Primary Chain Guard Studs & Nuts. 1912-1920 All Models.

These are the standard studs that use an inner nut to fasten them to the engine case.  (see pictures)  They fit cases from 1912 to 1920 that were not threaded.   Fits All 1912 - 1920 Singles & Twins Includes: Chain Guard Stud     472-12 Inside Case Nut        BO759            1/4" - 24 TPI  Outside Case Nut      472-15         5/64" - 32 TPI  Includes 2 Studs, 2 Outside Nuts, and 2 Inside Nuts.** After these are installed on your case, the inside threads should be spiked/mushroomed to insure the inside nuts will not come loose in the motor.