Below are the product details of Rotary Piston Vacuum Pump Models: KT-150C KT-300D KT-500D KT-850D Features: Full pumping speed down to 1 TorrCan operate continuously (at any pressure) up to 100 TorrUltimate pressure 10 Microns (McLeod Gauge)Adjustable gas ballast permits handling of condensable vaporsNo metal to metal contact in pumping chamberUnequaled durability, even in dirty applicationsCompact footprint designSimple installation, no special preparations requiredTriplex piston design provides quiet, vibration-free operation