I am selling an altitude tent that was used off and on during 2003 and 2004 and hasn't been used from that time to the present. I am only selling the generator, high altitude adapter, and tubing. A filter can be purchased if needed(I found it wasn't necessary for my usage/appx. $75), and the tent would need to be purchased from Hypoxico Inc.(appx. $175) as the plastic siding has started to separate from the rest of the tent. I will entertain all offers, but please be reasonable. This unit can be had for a low price, and I will even throw in a $100 gift certificate to a specialty running store for offers eclipsing the $1,000 mark(just call in to redeem it). Thanks for your time everyone and enjoy the running. I know I will after this stress fracture heals!!