The product is a vertical GSM intercom, made of stainless steel to monitor and manage your house/facility/warehouse entry points through your mobile device. It uses a high quality durable button along with water resistant speaker and microphone.
The SS91B-M product is a horizontal GSM intercom, designed for use with stainless steel. It uses a high quality durable button; the speaker & microphone is designed with a water repellent. It uses the GSM network, its main function when the visitor presses the call button (the call number can be added 3 sets out the number), it will dial to your phone for a call, in the call you can also use the phone to open the door