The Air Logic Division of Fred Knapp Engraving Company designs and manufactures a comprehensive line of pneumatic and vacuum ... control equipment. Components include Precision Pressure Regulators, Inline Filters, and Pressure & Vacuum Switches. Normally open & normally closed pressure and vacuum piloted valves are also featured. Pneumatic accessories include Preset Flow Controls, Needle Valves, Check Valves, and Orifice Restrictors. A complete line of Plastic Fittings is also available. read more