Used for sampling air volumes at low jet velocity. #7 "Ace-Safe" removable hose connections for easy connect/disconnect. Nozzle is calibrated to deliver 0.09 to 0.11 CFM at 30.5 cm (12 inches) H2O vacuum. Bottle has encircling graduations from 0 to 30 mL in 5 mL divisions. Complete item supplied with connectors and bushings.