DEF Doser Fluid Supply Module. For Cummins diesel engine applications. Also used on selected Peterbilt / Freightliner truck applications. DEF Doser / Urea Pump / Fluid Supply Module. Brand new replacement part. 1 x DEF Doser Fluid Supply Module. Replacement DEF doser supply module. Compatible with Cummins diesel applications. Helps supply DEF / urea fluid. 12V-24V voltage range. Direct replacement by part number. Durable construction for heavy duty truck use. Please check your original part number before ordering. Make sure A063W687 or 5509448 matches your old module. Please compare the connector, ports, and appearance with your original part. If you are not sure about compatibility, send us your VIN or old part photo for checking.