The RB500 is a high quality 500 plus CFM cartridge style dust collector. This heavy duty collector is built completely from 12 gauge steel and is 100% hand welded which ensures that it is very durable and has no seams that can leak dust. The pleated cartridge filter is loaded from the top of the cabinet which is a very unique design that insures a tight seal. Cleaning the filter is accomplished at the turn of a handle which releases air inside the filter to purge dust from the filter. The sump is then emptied from the bottom of the collector.