This universal sensor has 1 built-in reed switch plus 2 external zone inputs (open or closed circuit) which allows it to secure up to 3 doors, windows, etc. It also features Elk’s industry leading two-way technology.

Features:

• Compatible with ELK-M1XRFTWM two-way wireless transceivers
• Zones: Built-in reed, IN1, and IN3 (external contact terminals)
• Front and back tamper option
• 902 Mhz - 928 Mhz frequency hopping
• Maximum operating gap of reed: 1/2”
• 3V CR123A lithium battery