Liftmaster 770E garage door protector system, which provides extra safety by creating an infra-red beam across the garage door opening. If the beam is obstructed, then the door will not close. 

This product is compatible with the following Motorlift, LiftMaster and Chamberlain products:

• ML700
• ML850
• LM1000A
• LM1000A-GB
• LM800A
• LM600A
• LM600A-GB
• LM60
• LM80

Features:

• IR beam continuity indicated by red light LED 
• Sensors protected by heavy duty steel brackets
  
• Current Draw - 13 ma max
• Operating Voltage - 6 V
• Protection Rating - IP56
  

Included:

• Emitter
• Detector
• Brackets
• Wires
• Hardware