I agree with the other reviewer regard the flat side , it give flexibility for sand small part and make adjustment after change belt . as a add bonus , I be surprise to find that the shop vac hose attachment from Bosch that I purchase for my orbital sander work with this belt sander . this make it much quicker to achieve a smooth finish as it really help to pull the dust off the work surface . I recommend purchase the hose attachment . dust bag , regardless of the tool brand just do not work as well . all in all this be a fine product for a reasonable price .