REED Instruments R3100 Digital Manometer, Gauge / Differential, 100psi Measures gauge and differential pressure up to 100psi (11 selectable units of measure: psi, inH2O, bar, mbar, kPa, inHg, mmHg, ozin2, ftH2O, cmH2O, kgcm2) Displays pressure and real-time clock simultaneously Internal memory saves Max and Min measurements Low battery indicator and auto shut off Includes 2 Connection Hoses, Battery and Hard Carrying Case