The record power ac400 air filter has a two stage filtration system with pocket filters to provide filtration down to 1 micron it has 3 speeds and a timer function so you can leave the unit to run for a period after you have finished in the workshop both of which can be applied via the remote control useful for reducing nuisance dust particularly in small workshops provides effective filtration for workshops up to 113m input power 93 watt 18 hp filtration rate 409 cfmmin filtration 1 micron