Moeller Marine 033802-10 Aluminum Anti-Siphon Barb Anti-siphon valves, are required by Federal Law and the USCG on all permanent fuel tank installations. Use 15 Brass calibrated for HP 200 above and 30 Aluminum calibrated for HP below 200 HP. Deliver Coat Guardindustry standard anti-siphon protection on all gasoline-powered boats. Combines anti-siphon protection with a convenient hose barb design. Specifications 38 Barb 38 NPT Threading Aluminum Calibrated for HP below 200 California Residents