Edelbrock 5 10 psi Fuel Pressure Regulator Inline 10 An Inlets Outlet 6 AN Return Bypass Red Anodize 421998 Fast Removable Half Chin Bar Size:12 Wide Fast Removable Half Chin Bar (HCB) quickly and easily detachable to ensure fast access to breathing ways without the need to remove the helmet in case of emergency The swivel design lets the AN end be clocked to any position after the NPT threads are tightened Edelbrock has been committed to making the finest high performance products in the industry These carbureted fuel pressure regulators have an internal diaphragm made of fluorosilicone to ensure high temperature protection resulting in an extended life