Chamberlain C273 El Manual Del Propietario página 23

Invisible Light Beam
Protection Area
Facing the door from inside the garage
Safety Reversing Sensor
6" (15 cm) max. above floor
Carriage Bolt
1/4"-20 x 1/2"
1
2
Carriage Bolt
HARDWARE
Wing Nut
1/4"-20
No more
than 6" (15 cm)
3
Wing Nut