The CTI VDT-4200 Delivery Tunnel gives you great flexibility and economy in eliminating your particular odor problem. Odor specific vapors give you the most effective odor neutralization. The vapor concentrate container design gives you total control over the amount of vapor released and the length of time the concentrate will last. The vapor tunnel is designed to treat up to a 20,000 cu. ft. area. The tunnel can be placed on any flat surface or attached to the wall with simple Velcro tape. Comes with instructions.