This is a Digital Electronic Torque Wrench / Torque Screwdriver with a calibration certificate
What it’s used for:
Tightening bolts/nuts/screws to an exact torque value in N·m, instead of by feel. Critical for engines, electronics, machinery, or anything where “too tight” = stripped threads and “too loose” = things falling apart.
Key details from your pics:
1. Tool: Chrome ratchet head + blue ring. The 2 Toshiba AA batteries power the digital display/buzzer. When you hit the set torque, it beeps/vibrates and the screen shows the value.
2. Calibration Certificate: Stuck inside the case, dated 2017/4/28
• Unit: N·m = Newton-meters
• Test points: 6.00, 18.00, and 30.00 N·m
• Accuracy: Errors are all <0.22% → Very accurate. Ex: at 30.00 N·m it read 30.00, only +0.10% off.