Dynojet PCIII USB provides precise information for fine-tuning your FI Harley Davidson when upgrading the air cleaner and exhaust. Each PCIII unit includes a built-in microprocessor and a specific map designed to improve engine performance over stock. Dynojet continuously maps new calibrations for each bike, which are available for downloading at their website (www.powercommander.com) and if you do not have a computer, you can change the settings with three touch buttons on the faceplate of the unit. OEM-style wiring connectors with improved harness protection are supplied and no wiring modifications are required. All PCIII units include simple to follow instructions to install and adjust and USB (Universal Serial Bus) port provides an instant, problem-free way to connect your Power Commander to a computer.