I have a 1 month apex dos for sale that I dont need. DOS was purchased on April 16 2018 from BRS and I have a copy of the receipt to prove it anything. My wife tossed the box out by accident. Everything comes with the dos that comes in the box. The dos, power plug, calibration tube, and the tubing that I didn't use any of it. Selling for $260 shipped and PayPal fees included