My 1.5 x 8” DM can weighs 1.04 lbs with SiCo flash hider end cap and ASR QD Mount as for the difference seems to be the select OAL & ID (and the ID is NOT bored) mine is 1.375” ID and seems to be one of the more popular sizes if you go with the premium tube you can configure the internals with what ever cones you want DM, RSC etc as well as the mount, end cap and spacers. I have the DM hat cones 5 Ti, 2 SS for The first two from the brake you need SS.