Part of Hold Fast"s Vacuum Chucking System. Used specifically for woodworking applications, particularly vacuum chucking on a lathe. Uses a pair of unique high efficiency venturi elements to generate the required vacuum. Unit is low maintenance because there are no moving parts.The generator can be driven by any standard air compressor that provides at least 2.5cfm at 55-65 psi. Comes with a built in pressure regulator. Can be conveniently mounted close to the work area with velcro, double-stick tape, or magnets. USA