TM 55-4920-328-13 Table  13.  Leading Particulars of Test Trailer Assembly - Continued. Figure and Index No. 56, Figure Power Supply Unit 7-18 Quantity Required 6 Height 1.75 in. Width 3.00 in. Length 3.50 in. Input Voltage 117v ac, 60 Hz Output Voltage 0 to 30v dc Output Current 100 ma dc 170, Figure Fuel Pressure Gage Switch S1 7-24 Length 3.55 in. Diameter 1.90 in. Weight 6 oz (max) Medium MIL-T-5624, JP-4 or JP-5 Switch Type spdt Input Voltage 28v dc Input Current 3.5 amp Actuation Decreasing Pressure 7.0 psig or more Increasing Pressure 8.0 psig or less Pressure Port 7/16-20 UNF-3B Mating Connector MS3106-10SL-3S 181, Figure Air Pressure Gage Switch S3 7-24 Length 3.55 in. Diameter 1.90 in. Weight 6 oz (max) Medium air Switch Type spdt Input Voltage 28v dc Input Current 3.5 amp Actuation Increasing Pressure 4.5 psig or less Decreasing Pressure 4.0 psig or more Pressure Port 7/16-20 UNF-3B Mating Connector MS3106-10SL-3B 184C, Figure Oil Pressure Gage Switch S2 7-24 Length 3.55 in. Diameter 1.90 in. Weight 6 oz (max) Medium Engine Oil MIL-L-23699 Switch Type spdt Input Voltage 28v dc Input Current 3.5 amp Actuation 3.5 amp Increasing Pressure 28.0 psig or less Decreasing Pressure 25.0 psig or more Pressure Port 7/i620 UNF-3B Mating Connector MS3106-1 OSL-3S 1-84