Remove heat shields, install bung and tune when completed, use included screw and copper washer to seal bung and then replace heat shield for unaltered finishComplete bung kit includes 1 hydraulic insertion tool, 1 drill bit, 2 O2 sampler blocks, tubing, 25 rivnuts, 25 screws and, 25 copper washersNo pump or sampling tube required and allows both cylinders to easily be monitored at the same time and no weldingAdds 18 mm x 1.5'' threaded bungsMade in the USA