A fitting type damper and a process thereof being capable of increasing largely slipping torque in strength are ones that the large slipping torque can be increased not only when the damper is a new product but also after a heat aging test and/or a durability test are performed. And, the damper is one that γ-mercaptopropyltrimethoxysilane 4, which is an organosilane used as a non-slip agent, is adhered and fitted between a hub 1 formed by some metal parts and a rubber elastic body 3, and between a inertia mass body 2 formed by some metal parts and the rubber elastic body 3.