1" OD Drive Roller with the 12 mm x 1.50 male right hand threads.
As of 3-21-16 the 1" OD Drive rollers can be used with the Smaller 54 mm or 2-1/8" clutch drums with the 12mm x 1.5 threads and now with the 78mm clutch drum that has the welded hub with 12 mm x 1.50 threads.
This Drive roller is Heat Treated and Zinc Plated. Uses 5/8" bearings on both ends.
Below is a lot of good info and fast links:
This can be used with both the smaller 54 mm & the larger 78 mm Clutch Drum with the 12 mm x 1.5 right hand female threads.
The clutch drum is Not included. If you need one click on the link below.