A dust separator works by being connected between the machine and extractor. This dust separator has a capacity of 110L so is considerably bigger than most small extractors. It can also be used on machines that create fine dusts even when the extractor would not normally be suitable for this type of machine. Made of sheet steel and fitted with castors, this is a sturdy unit. It has 63mm inlet and outlet fixtures, and would best be suited for use with a vacuum extractor, such as the Axminster Trade NV750. Steel clips hold the lid on and a partial vacuum is created between the waste bag and the inside of the drum to ensure complete filling. A handy window shows when it is full. Well made and useful. N.B. Some assembly required.