2.4GHz Mini Portable Dual Way Voice Intercom Wireless Doorbell Interphone System

Description: This is a portable doorbell system for home, factory, hotel, market, and more. Built in microphone and speaker allow super sound quality for dual way communication. Simple and small design, easy to use. Specifications: Indoor Bell Power Supply: Rechargeable Lithium Battery Input Interface: Micro USB Wireless Frequency: 467.6375MHz Transmission Distance: 300m Working Time: > 6 Months Working Temperature: to 20 ~ 55 Size: Approx. 100 * 60 * 16mm / 3.9 * 2.4 * 0.6in Package Size: Approx. 170 * 120 * 25mm / 6.7 * 4.7 * 1.0in Package Weight: 150g Outdoor Bell Power Supply: 4 x AAA Batteries (NOT Included.) Wireless Frequency: 467.6375MHz Transmission Distance: 5 ~ 50m Working Time: 48h Working Temperature: to 20 ~ 55 Size: Approx. 100 * 60 * 16mm / 3.9 * 2.4 * 0.6in Package Size: Approx. 170 * 120 * 25mm / 6.7 * 4.7 * 1.0in Package Weight: 150g   Package List: 1 * Indoor Bell 1 * Outdoor Bell 1 * USB Cable 1 * Screw Driver 1 * User Manual