Nitrous Oxide System - NOS Nitrous Bottle (14720-PNOS)NOS Nitrous Bottles are offered in a variety of sizes, finishes, and constructions to suit your needs. Approved by the D. O. T. and CGA, NOS bottles feature a built in siphon tube! Note: All bottles shipped empty. 2. 5 lb Bottles For Optimum Weight Reduction Distinctive High Tech Look DOT Approved Carbon Fiber Wrapped Bottle Weighs Half Of Standard Capacity (lbs.) 2. 5 Color Polished Blow Down Tube Included No Bottle Finish Polished Bottle Material