This O-Ring with part number 305123 is designed for use in Evinrude and Johnson outboard engines. It is an essential component for maintaining the proper seal between the fuel pump and carburetor. The O-Ring is made by Johnson, a reputable brand known for producing high-quality marine engine parts. The part is compatible with a range of Evinrude and Johnson outboard engines and can be easily installed with minimal mechanical knowledge. Whether you are repairing or maintaining your boat's engine, this O-Ring is a reliable and cost-effective choice.