FEATURE- Suitable for people who is physical dishabilles , blind man, security guard, handicapped, multi-store manpower support, huge villa. - Simple installation. - Instant alert by beep, vibration and flashing icon. - Two stage shock sensor. - Four-zone relay contact output. - Immediately informed by a sound or vibration though wireless transmitter, when house phone ring, door bell rings ,or when there is fire alarm or somebody intrude your house.