â·ÃÊͺ¶ÒÁÃÒ¤Ò The Extech HD755 differential pressure manometer measures gauge and differential pressure in the range of +/-0.5 psi. HD755: Differential Pressure Manometer (0.5psi) Low range (0 to 0.5psi), High Resolution (0.001psi) Gauge/Differential Pressure meter Features: ±0.5psi range, 11 Selectable units of measure Max/Min/Avg recording and Relative time stamp Data Hold, Auto power off and Zero function Large LCD display with backlighting Heavy duty, double-molded housing Built-in USB port (Windows® compatible PC software and cable included) Specifications: Specifications Specification Range Resolution inH2O 13.85 0.01 psi 0.5 0.001 mbar 34.47 0.01 kPa 3.447 0.001 inHG 1.018 0.001 mmHG 25.86 0.01 ozin² 8.00 0.01 ftH2O 1.154 0.001 cmH2O 2.59 0.01 kgcm² 0.035 0.001 bar 0.034 0.001 Dimensions / Weight 8.2x2.9x1.9" (210 x 75 x 50 mm) / 9.8oz (280g) Extech HD755 Manometer Pressure Meter à¤Ã×èͧÇÑ´¤ÇÒÁ´Ñ¹ÅÁ