Welcome to Keystone Electronics
Manufacturer and distributor professional PSTN and GSM Auto-Dialers, a wide range of Low Power/Low Cost Radio Transmitters and Receivers, and a selection of stand-alone WiFi Sensors and Smart WiFi Plugs.

PSTN & GSM AUTO DIALERS
PSTN and GSM Auto Dialers that play a user programmable Voice Message or send an SMS to up to nine different telephone numbers.
