2gig GCPOTS Telephone Line Module for CP21-345E (Black) GO!Control Security and Home Automation Control Panel Improved Z-WAVE New DC Power Receptacle All 2Gig product requires a 2Gig GO!Control panel and a subscription to alarm.com for full functionality 2Gig products are intended for professional installation only Two-Way-Voice capable without a cellular radio^Central station monitoring without a cellular radio^Primary or backup communications option when used with a cellular radio^Full line seizure when used with a properly connected RJ31X jack^Terminals for connecting lineman's "buttset"