Features:

• Uni-directional valve function assures compliance and eliminates false errors.
• Uni-directional valve also reduce chance of saliva and foreign particle that may adversely affect the sensor.
• Can be used as both disposable and reuseable after rinsing.
• Made of hard rubber to ensure a good seal under the user's lips.

Note that the mouthpieces are sold in quantities of 10.
By selecting "1", you are purchasing 10 pieces.
By selecting "2", you are purchasing 20 pieces.

Contact us if you have any doubts!