Macro line hose is the easiest hose to work with when running air for you marker. Cut the ends straight with a razor blade (not scissors) and slide it in to a Macro Line Fitting. You"re good to go! Keep CO2 tanks out of hot cars and sunlight when connected to a Macro Line Hose. The hose can burst when room temperature CO2 pressures are exceeded. Better get a couple of these just in case. **If w"ere out of the color that you order we"ll replace it with black and ship your order unless you specifically request *No Substitutions* in your order comments at the end fo the order.