... sites. Calls can be made/received through PSTN (telephone line) or VoIP which can help operators reduce investment ... such as parks, streets, resorts, etc. Specifications - EnvironmentalOperating Temperature-25°C ~ +55°CRelative Humidity10% ~ 95%Noise≤ 60 dB ... backlight supported, shock resistance ≥ 4,000NPull Resistance of Handset CordNot less than 150kgLifespan of Card Reader> 500,000 ...