The Briggs & Stratton 590406 Piston Assembly helps convert combustion pressure into mechanical movement for dependable engine operation. Positioned inside the cylinder, the piston moves up and down as the fuel-air mixture burns, transferring force through the connecting rod to the crankshaft. This movement supports the power required to operate the equipment while maintaining proper c... https://www.wholetoolbox.com/briggs-stratton-590406-piston-assembly/590406.html