1. 4~8 Co Lines 16~64 Exts 2. Eight-party conference call 3. Caller ... , prepaid Detailed Product DescriptionGroup Phone Info Capacity:Basic is 4 Lines 16 Extensions.Can be up to 8 and 64 respectively ... Item)By the function,system can monitor all of Co.Lines and Extension Status,also can monitor,program,revise and call ...