Sigma 342A is a compact, high-precision ultrasonic thickness gauge designed for accurate non-destructive measurement of material thickness, particularly in marine and industrial environments.It combines advanced single-chip microprocessor technology with user-friendly functionality for reliable field measurements.

Key Features
High Resolution: Measurement resolution up to 0.01 mm for precise readings.
Wide Measuring Range:
1.0–350 mm (45# Steel)
Optional 0.8–500 mm (45# Steel)
Dual Frequency Operation: 5 MHz standard / 2.5 MHz (with special probe).
Continuous & Single Measurement Modes
Sound Velocity Measurement & Adjustment
21 preset material velocities
Manual adjustment (1000–9999 m/s)
Automatic Probe Recognition
Data Storage: Up to 100 measurements
Custom Thickness Alarm with buzzer alert
MAX / MIN / AVG display
Self-Calibration Function
Accuracy & Performance
±0.05 mm for thickness <10 mm
≤±(0.01 + H/200) mm for 10–99 mm
≤±(0.1 + H/100) mm for >100 mm
Minimum tube curvature: Ø20 × 3 mm (45# Steel)
Design & Power
Lightweight: 153 g (without batteries)
Compact Dimensions: 72 × 135 × 36 mm
Power Supply: 3 × 1.5V AA alkaline batteries (approx. 20 hours operation)
Operating Temperature:
Main unit: 0°C to 40°C
Probe: 0°C to 60°C

Applications
Marine hull thickness inspections
Corrosion monitoring
Pressure vessels and pipelines
Structural steel evaluation
Preventive maintenance programs

Its combination of portability, precision, and intelligent measurement functions makes it a practical solution for surveyors, engineers, and maintenance professionals requiring dependable ultrasonic thickness measurements in demanding environments.