This arm is the most commonly replaced part on the 28366 belt sander.
3M 28368 Standard Attachment Arm For 28366 0.5 in. x 18 in. File Belt Sander
3M 28369 Thin Attachment Arm For 1/2 in x 18 in Belts, 1 Per Case
Dynabrade Products 11206 3/4" X 5/8" Rubber Contact Arm [for Use With 3/4" W X
ARB Air Locker Manifold Kit 171503 For Use with CKMTA 12 or 24 Twin Compressor
3m 3M-28368 Standard File Belt Sander Attachment Arm