Cummins ISX15 / QSX15 / X15 Torque Lock Injector Cup KitCummins ISX15 QSX15 X15 Torque Lock Injector Cup Kit Permanent Solution to Fuel & Coolant Cross Contamination The Industrial Injection Torque Lock Injector Cup Kit is the proven solution for one of the most common failures on Cummins ISX15, QSX15, and X15 engines: leaking press fit injector cups. If youre dealing with coolant in fuel on your Cummins ISX15, the root cause is often a loose factory press fit injector cup. This kit provides a permanent