Line Powered Off Hook, Ring and Message Waiting Indicator. The Viking model LPL-1 connects to any standard analog phone line or phone system s analog station port to provide visual Ring Indication, On The Phone indication and Message Waiting indication. The LPL-1 won t have you guessing which phone is ringing in busy offices. The large flashing LED can be seen up to 100 feet away. When used with a headset on an analog phone, you can end those nagging interruptions that occur when associates don t realize you are on the phone because you are using a headset. The LPL-1 will light steady indicating to everyone that you are on the phone, flash during ringing or fast flash to indicate message waiting. Caution: The LPL-1 is not compatible with digital station ports. When installed on phone systems with standard 90VDC message waiting voltage. Applications Hearing impaired locations Call centers Telemarketing Product support groups Office cubicles CO based voice messaging Purchasing departments Sales offices Features Displays Ringing, On-The-Phone or Message Waiting on analog phone lines or PABX stations LED visible up to 100 ft (30m) Telephone line powered Attractive new compact package Connects with a modular cord or screw terminals Easy to install Easy wall mounting with included doubleback tape.