Wireless GSM Repeater/ transceiver

Wireless GSM Repeater/Transceiver Features: Based on GSM 900/1800MHz or 850/1900MHz. Support reverse polarity Can connect to PBX. with Li-battery, support standby time over 18hours. 5. with 2RJ 11 phone port, can be connect with extension; Main Functions: 1. Suitable for GSM 900/1800MHz or 850/1900MHz, using SIM card 2. Making & answering calls after connecting to telephone set 3. Available to connect with telephone set, Billing machine, etc 4. Supports the functions of