This is the usual 1/4" (.172" or 4.37mm ID) tubing that you already know and love. It's safe for pressure through 400+psi (when paired with compression fittings). Use for the main supply run from pump to downstream hardware. (Huge flow systems may be better served with 3/8 tubing from tank to pump.) Neutral black color makes discrete packaging easy and clean.
Or, for heavy methanol concentrations and fuel system-grade security, go with our black braided 4AN flex hose instead. See our 3/16" Teflon Nozzle Connection Hose for the most modern way to supply each nozzle holder.
Note: Priced per foot.