The Series 477B Handheld Digital Manometer is a precision instrument designed for accurate measurement of positive, negative, and differential air pressures. With an impressive ±0.1% full-scale accuracy (at 60-78°F/15.6-25.6°C), it outperforms standard manometers in reliability.

Available in ranges from 0-20 in w.c. to 0-100 psi, the device features the ability to store 40 readings, the option for seven pressure units, and both visual/audible overpressure alarms. Its compact, battery-powered design makes it ideal for field use in HVAC, industrial diagnostics, and compressed air systems.

• ±0.1% FS accuracy in optimal temperatures (15.6-25.6°C), ±1% in extended ranges (0-40°C)
• ±0.1% FS hysteresis for consistent readings across pressure cycles

• Measures positive, negative, or differential pressure in 7 selectable units (in w.c., psi, kPa, mbar, etc.)
• Stores 40 readings for later recall, with hold function for freezing measurements

• Backlit 4-digit LCD (0.425"H digits) for low-light visibility
• Visual/audible overpressure alarms to prevent damage in extreme conditions

• Lightweight (10.2 oz/289 g) with 9V alkaline battery (included, user-replaceable)
• Long battery life for extended field operations

• Operating temperature: 0-140°F (-17.8-60°C); storage: -4-176°F (-20-80°C)
• Barbed/compression fittings for 1/8"-3/16" ID tubing (model-dependent)