Ever seen a BHJ damper before? This one is a 7-inch, 8.7 SFI-rated unit for small-block Chevys. It is internally balanced and has a billet steel outer ring and a billet steel hub. The damper is elastomer-style so there is rubber between the hub and the inertia ring. To get an SFI rating, the damper must be spun to a specific rpm to see if it explodes, and it must be designed so the inertia ring does not come off the hub if the elastomer fails. The BHJ damper uses a machined surface that traps the ring so it can’t exit the vehicle.