Image 1 of 2 Image 2 of 2 Additel 9240A Differential Pressure Gauge Holder with Built-in Additional Volume for Low Pressure Control $660.00 Add To Cart Added! Differential pressure gauge holder with built-in additional volume for low pressure control. Differential pressure gauge holder with built-in additional volume for low pressure control. You Might Also Like Additel 100-HTK Hose Test Kit from $121.00 Additel ADT912-N-KIT - Test kit for Additel 912 and 912A (Hose barb fitting, hose, etc), 1/4 NPT M $239.00 Additel 9901-901 - Carrying case for Additel 901 Generator, and two gauges (No label) $398.00 Additel 917-MK Maintenance Kit for ADT917 Generator $111.00 Additel 9816-UK Power Adapter for ADT760 Calibrator $123.00