You all know that I love my NO2 I have had it over 2.5 years now, and it still works well. This one here is new. In the Box! I opened it, and put the battery in and tried it once. I used my own tube, so the one in the box is unused. BUT... I did pre-soak the tube in hot water as per the NO2 Manual... I did this for you so it is ready to go- odor free! The unit was used for a session, and then it got brand new "NO2 Screens" installed on both top and bottom.. so you will not receive a unit with any residues or particles. The Deal... $110 shipped to your door. I will speak here in generalities about the unit as a whole... Details of sale will be discussed in Private Message. Payment can be made via PayPal.