- Viking ring generator- Reshapes troublesome distorted ringing signals- Boosts ringing power of analog ISDN Terminal Adapter Ports- Use with Viking’s doorboxes to increase the number of phones they can ring- Boost ring power on telephone lines or analog PABX/KSU stations that are weak or fail - True Sine wave ring signal output- Boosts ring to 4 REN- Caller ID patible- Easy installation- Compatible with distinctive ringing services- Will not affect normal line operation- Reshapes troublesome square wave ringing- Not patible with pulse dialing VKRG4