During the landing rollout, the pilot applied brakes and the airplane nosed over coming to rest in an inverted position on the runway. The fuselage, vertical stabilizer, and left wing struts were substantially damaged. Per a photograph provided to the investigator-in charge (IIC), the airplane was not equipped with the manufacture’s optional landing gear extensions, which extend the main wheels forward. The pilot reported no preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation.