Dual Tube Connectors. On the top of the differential pressure gauge there are two ports, one for testing positive pressure and the other for testing negative pressure. Easy to use and accurate with a large display.
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HT636 Manometer Digital Surface Pressure Difference Measure Wind Air Pressure Differential Pressure Gauge Meter 12 Pressure Unit
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Kane 3200 High Accuracy Differential Pressure Meter
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UNI-T Digital Manometer UT366A Air Pressure Gauge Handheld Pressure Differential Detector Pressure Measuring Device
Aliexpress UK
✅【High Accuracy】Test air pressure ±13.79 kPa / ±2.000Psi with ±0.3%FS high accuracy. ±0.25%FS repeatability. 11 gas measurement units optional, including mmHg, inHg, ftH₂O, cmH₂O, KPa, Mbar, Bar, Psi, Kgcm², inH₂O, and Ozin². Over-range indication available. ✅【Dual Port Design】Equipped with two tube connector(3.18mm diameter), digital manometer 189A is capable to measure static pressure(positive/negative) and differential gas pressure levels accurately. An essential tool to obtain accurate pressure readings and diagnose issues in HVAC heating, ventilation, and air conditioning systems. ✅【Data Record & Zero-out】Press"REC" button to record and review max / min / average air pressure data; Short-press "HOLD” button to freeze measurement data and Long-press 5 seconds to clear out remaining dat.
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Tensiometer Heart Rate Pulse Meter BP Monitor Healthy Digital Arm Blood Pressure Meter Cuff Medical Automatic Pressure Tonometer
Aliexpress UK
✅ Versatile & Precise: ➠ Measures differential, positive, and negative pressure with ±0.3% FS accuracy—ideal for HVAC diagnostics, lab research, and industrial maintenance. ➠ 12 Units Conversion at a button press (e.g., switch between psi, bar, kPa instantly). ✅ User-Friendly Design: ➠ Backlit LCD with clear symbols (HOLD, BAT, REC.) for easy reading in dark environments. ➠ One-Touch Data Hold & Recording—capture peak values or track trends effortlessly. ✅ Durable & Portable: ➠ Compact size fits in toolkits; rugged construction withstands on-site use. ➠ Auto-Shutdown saves battery life during long projects. ✅ Troubleshooting Ready: ➠ ERR Alerts warn of overpressure (ERR1) or underpressure (ERR2), preventing system damage.
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Tensiometer Heart Rate Pulse Meter BP Monitor Healthy Digital Arm Blood Pressure Meter Cuff Medical Automatic Pressure Tonometer
Aliexpress UK
Model No 3500 ( high pressure ).
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ABX Tensiometer Heart Rate Meter BP Monitor Healthy Digital Arm Blood Pressure Meter Cuff Medical Automatic Pressure Tonometer
Aliexpress UK
▶️Wide Applications Range: Suitbale for vacuum degree negative pressure testing of the intake manifold, brake booster pressure testing, negetive pressure testing of the crankcase, exhaust valve negative pressure testing, etc.
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Tensiometer Heart Rate Pulse Meter BP Monitor Healthy Digital Arm Blood Pressure Meter Cuff Medical Automatic Pressure Tonometer
Aliexpress UK
Accuracy: ±0.3%FSO (at 25°C). press this button to switch pressure unit. Power on status press this button to hold reading display and another operation. press this button over 2 seconds to make reading zero.
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Electric Tonometer Arm Blood Pressure Monitor Digital Heart Beat Rate Pulse Meter Backlight Automatic Home Blood Pressure Meter
Aliexpress UK
💡 BONUS: TheDIF mode lets you compare two pressure points instantly – perfect for filter checks or system diagnostics! ✅HVAC systems – Optimize airflow & duct pressure. ✅Lab/cleanrooms – Precise gas pressure monitoring.
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Tensiometer Heart Rate Pulse Meter BP Monitor Healthy Digital Arm Blood Pressure Meter Cuff Medical Automatic Pressure Tonometer
Aliexpress UK