Charging shows red light, full green light and working yellow light When the standing wave is greater than 25, the buzzer prompts intermittently If the standing wave is greater than 30, the buzzer will prompt continuously Battery undervoltage, buzzer continuous prompt The version information is displayed after on, and the standing wave measurement interface and battery are displayed after 3 seconds. English interface Frequency range: 18mhz-50mhz Measurement range: 05w-120w (up to 210W, long-time FM, am, CW mode is recommended to be less than 120W, SSB mode is optional) Measurement accuracy: less than +/- 5% Standing wave range: 10-9999 Access interface: sl16 (block m) Charging interface: type-C Aluminum alloy shell size: 63mm x 88mm x 38mm (excluding protruding parts) Battery capacity: 1000mah Insertion loss: less than 01dB Colour: black Material: aluminum alloy Package Contents: 1 * SWR HF Short Wave Standing Wave Meter Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.