I was looking to improve the dust collection on my Rigid belt sander (where the belt is standing on it's side). OEM dust collection is a tiny port in the table to collect your shop vac to.
Having just upgraded to 6" duct and seeing the power that the duct size has on collector performance, there's no way I was going to use the small port. And, I had all these extra 4" fittings laying around. So, with the S&D elbow, I can still get to the back of the sander when it's parked against the wall, and quickly/easily pull that 4" hose to use on other tools in the vicinity. The 4" flexible hose has a threaded quick connect that fits perfectly inside the elbow.
sander dc elbow.jpg