Signal Generator"Product features. 1. Use of high quality materials, durable 2. Compact size and exquisite appearance 3. Easy to use 4. High efficiency, reliable and stable performance 5. Wide range of applications Parameters. Active current output: 0-22mA (min. output approx. 0.1mA), load 0-550 Passive current output: 0-22mA (min. output approx. 0.1mA), external power supply 15 - -30V, load 0-550 Voltage output: 0V-12 V (min. output approx. 0.05V) 24V voltage output: drive current 35mA, do not use more than 35mA Battery version lithium battery powered, rechargeable; no battery version plugged directly into 5v charger Battery undervoltage indication, when the undervoltage indicator lights up, please switch off and recharge in time If not in use for a long time, recharge at least once every 2 months to prevent battery damage Use MICRO USB port for power supply or charging Use ring mirror: 0C- 50C without condensation Package list. Signal generator*1"