Attach the Nalgene 6140-0010 Polypropylene Faucet Aspirator Vacuum Pump-Filter Pump directly to sink faucets for vacuum draw. Attaches to a standard faucet with 3/8″ NPT connecting thread for easy installation. It can draw 11.5L air per minute at a water flow rate of 6.5L per minute. It operates efficiently with water pressures as low as 7.5 psig for minimum water consumption. Ultimate achievable vacuum of 28.5″ (724mm) Hg. It comes with an integral check valve that prevents loss of vacuum when water source is disrupted and prevents backflow. Discharge end equipped with 4.75″ (12cm) length of tubing to direct discharge water toward the drain or to allow attachment to additional discharge tubing.