Microcontroller Based PBX System with 9 Extensions has a built-in battery charger circuit which can be connected to 24VDC, 7AH battery. Microcontroller Based PBX System with 9 Extensions is manufactured by Matrix Telecom Private Limited which is an ISO 9001 accredited company. Matrix Telecom Private Limited also manufactures various types of cutting-edge telecom products like IP-PBX, universal gateways, VoIP Gateways and terminals, GSM FCTs, GSM gateways, access control, time-attendance systems and fire alarm systems. The Microcontroller Based PBX System with 9 Extensions, Model VISION309P, offers intelligent features like auto redial, auto call back, call-follow-me, conference, abbreviated dialling, hotline, etc. And finds an application in offices. This System allows 3 people to converse in a single conference. This System prevents misuse of long distance and international dialling to control telephone cost. This System has push type connector with dimension 26.7 X 28.5 X 8.0cm and weight 2.0kg.