High flow one-way check valves designed to prevent back-flow with minimal pressure drop. Ideal to prevent drain back after the fuel pump is turned off, or when dual pumps are used and both pumps may not run simultaneously. CNC-machined billet aluminum and Type II bright dip black anodized finish. AN-06 male inlet, ORB-06 female outlet connections. Ideal configuration for easy installation into filter or fuel pump outlet port, no need for additional lines, hose-ends or fittings. Suitable for use with gasoline fuels only, not alcohol compatible. Use AN-06 o-rings P/N 15621 for installation into ORB-06 port.