Dash 6 push-on hose with a bore of around 9.65mm, cut to the length you order. This is the most-used size in a push-on system, covering fuel feed and return, small oil lines and coolant runs on most builds. It is intended for push-lock barbed hose ends, which are pushed on by hand and held by the barb, so assembly needs no clamps, crimping or specialist tools. A little assembly lube helps the hose slide over the barb. Because it is rubber hose it must not be paired with PTFE or braided hose ends, and a clamp is sensible where the line runs under real pressure.