Concentrator with 4 x 8 line 911 capability

4 line inputs and 8 device ports - allows up to 8 devices to share 4 telephone lines. Units can be paralleled for sharing the same 4 lines with 16 or more devices.

If a particular device is busied out because all lines are already occupied by other devices, emergency 911 calls can still be made by that busied out device. This is useful in jurisdictions where 911 call capability is mandatory.