• Oil-free pressure/vacuum pumps are used for processes including filtering, desiccating, cell harvesting, vacuum blotting, aspirating, degassing and distilling. • Designed for continuous duty operation with the quietness. • For applications needing a rough vacuum 648 to 752 mm Hg (25.5 to 29.6 in. Hg) and free air displacement up to 201 liters/min (7.1 cfm). • Motors are thermally protected. • Standard-duty pumps are protected from moisture and corrosion. They use a WOB-L® piston pumping mechanism. • Liquid trap attached to each of these pumps traps water if it is accidentally drawn into the line. • These pumps are not recommended for pumping acid, bases or organic vapours. • Chemical-duty pumps use corrosion-resistant PTFE on all wetted surfaces. This allows pumps to withstand aggressive solvent, base and acid vapours. • Discharge air noise is muffled with a silencer on both types of pumps. • On model 741-421-24, a gas ballast valve minimizes vapour condensation inside the pump. • Power: 115V. CSA Approved. 1 year warranty. • All pumps are supplied with a vacuum gauge, carrying handle, suction cup feet, line cord and on/off switch.