The HP9015 Performance Module fits 15L Cummins Tier IV Final Engines. This diesel performance module is designed for fuel economy with up to 30% increase in hp and fuel savings up to 10%-20%. Adjustable from your electronic device via our Ag Diesel Solutions Bluetooth Connect App or the included mechanical switch. You can change your settings from stock, +15% & +30% hp. The module doesn’t flash the ECM, instead it receives the data from the ECM, optimizes the signal to the engine improving the fuel efficiency and power. So it does indeed promise to pay for itself in pretty short order. Plug-and-play connectivity means there’s no need to cut, splice or modify engine wiring.