1、With 9 LED indicators, real time display of various information, such as signal display, call status, etc., let you know the melting situation in time 2、It has the function of a meter, and a charging alarm mode. With multiple billing functions, it can be used as a public phone, which completely eliminates the meter and saves costs 3、Adopt 300W communication module, good signal, good long-term working stability, clear sound quality, no noise in the call, no dropped call, strong signal reception even in remote mountainous areas 4、The large LCD screen can display the signal reception strength, specific time, call history, call time, phone bill, etc., all kinds of information are clear at a glance 5、Adopt anti noise circuit design, anti noise and anti‑interference. 24 hour work, built in watchdog automatic detection, all round avoidance of collisions, prevent collisions, and avoid missed calls Item Type: GSM Dialer Product Size: Approx. 16 x 10 x 3cm / 6.3 x 3.94 x 1.18in Weight: Approx. 420g / 14.82oz Material: ABS Working Mode: GSM 900MHz/1800MHz dual frequency Peak Power: 0.5 W Power Consumption: static ≤ 25 mA, emission ≤ 600 mA Sensitivity: -104 dB Ambient Temperature: 0 ℃~40 ℃ Working Humidity: 45%~90% (under non condensing conditions) Atmospheric Pressure: 86~106 Pka Environmental Noise: <60 dB DC Power Supply: 5V 1 x GSM Dialer 1 x Connection Line 1 x Data Line 1 x American Plug 1 x English Manual