Piston Ring Kit for 13HP Engine This piston ring kit is designed to fit 13HP engines.It is suitable for use in models commonly referenced as GX390 and 188F engine types.The package includes all necessary components as displayed on the product page. Please take into account that slight variations in measurement may occur due to manufacturing tolerances.Color differences may also appear due to and screen settings during photography but do not affect the functionality of the item. Compatibility Disclaimer: This is an aftermarket replacement part.Any brand names or model designations mentioned are used solely for the purpose of demonstrating compatibility.