QTY Per Sell: 1 Drive's multi-threaded lid ensures a secure fit every time, preventing leaks and service calls Audible back pressure alarm activates at 6 psiDrive's multi-threaded lid ensures a secure fit every-time, preventing leaks and service callsAudible back pressure alarm activates at 6 psi aluminum fitting in stem: it eliminates shredded aluminum diffuser so often found in lower quality models Soft plastic diffuser reduces clogging due to mineral build-up Translucent jar provides improved visibility of jar contents Humidifier bottle lid is colored green/yellow, making it easy to tell patients on the phone how to change the bottle Bottle has a 500 mL water capacity Bottle fill line is very easy to see There are finger grips at the top of the bottle, making the lid easier to screw on/off for the patient
