This type of narrow band exhaust clamp is a very simple, effective way when connecting your exhaust systems with 360°seal but no damage on the pipe, regular exhaust clamps will distort the tubes when you try to tighten to make it more seal. With an I shape reaction block, which has arc curved face, together with a bolt, the clamp can create a complete "Inner circle Seal", helping avoid any leak of exhaust gas or noise.