Ametek Crystal M1 [M1-30PSI] Digital Pressure Gauge, 1/4" NPT male, 0 to 30 PSI. The M1 digital pressure gauge maintains 0.2% of reading accuracy from -10˚ to 50˚C. Accuracy is not affected by dropping, over-pressure, vibration, temperature, or rapid pressure change. Available as a 30 psi digital pressure manometer. One wide range M1 digital pressure gauge replaces up to five 0.25% mechanical gauges with 0.2% of reading accuracy.