The 2GSM Module consists of 2 GMS for use in the U50 and U100 models of CooVox as well as the Zycoo Asterisk P Appliances. It allows the use of a total of 6 SIM Cards for companies that require this type of lines such as Call Centers, Travel Agencies and Sales of Minutes. These modules can be used in slot 1 or slot 2 as both support it giving the option of having a total of 6 GSM if required. In combination with the 2GSM Module you can have 4 SIM Cards for the solution that requires such combination for future expansion.