Piston kits have a 1 year warranty from date of purchase. This warranty covers this piston kit only. Our factory does several quality control checks to ensure that these kits are made to O.E.M. specifications and components are top quality. However, because of the nature of piston kits, we cannot guarantee that replacing your chain saw piston will solve your saw problems. Proper installation is critical, and should be done by a trained chain saw mechanic to O.E.M. specifications. Remember, 99% of all piston failures are due to operator error, which includes incorrect carburetor settings, incorrect fuel mixture or improper air filter maintenance.