As with some other reviewers, we were having problems with our garage door openers. The colder the weather, the more often the lights on the opener would flash and the door would not close. There was nothing blocking the sensor beam, and the beam was aligned properly, but the door would not close. Leaving for work in zero degree weather, this was more than a little frustrating. We would have to hold the button on the wall down to get the door to close and go out another door. Then the weather would improve, the door would function properly, and all was well.

We were considering biting the bullet and buying new garage door openers last winter when we were having issues again, but I came across some reviews from people who had a problem similar to ours. They had replaced their sensors to fix the issue. Worth a try! I bought the first set, installed them, and the problem was gone. Shortly thereafter bought another set for our second garage door. They were very easy to install.

Our 20+ year old Lift Master Professional became sporadic when we'd try to close it - sometimes it would close, other times it would refuse and blink the light 10 times, as if something was blocking it. Worse, when something was blocking it, it wouldn't care and close anyway.
I determined the safety sensors were going bad, and had a hard time finding the exact version which had two green LED's. Based on other reviews I figured I'd try these, and in less than five minutes of splicing wires I had these working. I didn't even use the brackets they came with, but with the old brackets the LEDs face inward. Also, keep in mind the yellow led one is the sending sensor, and green LED's is the receiver, in case it matters.
Old garage door opener works as expected now for under $40 and 5 minutes!

My original sensors (pictured) each had a green light, instead of one green and one orange. This means my door opener was older than the late 90's and onward they say these are compatible with, but an OEM replacement for the ones pictured were over $150, and these were less than a third of the price so I figured it was worth a shot, as I saw others say it SHOULD work but no guarantees, so I wanted to write this to help others know that yes, indeed it does work.

Installation was VERY simple and took me less than 15 minutes total and that's with two cars in the garage to maneuver around with below freezing temperatures outside as well.

Highly recommend these, fixed my issues with my receiving sensor not working when it got very cold.

Does your father in law's Garage door not want to close?
Does the Chamberlain lights flash like 10 times at you?

Did you notice your father in law RAN OVER the transmitting sensor going into the garage cuz he mounted it so far out it catches the passenger side tire?

Then You'll need these sensors, a reciprocating saw, Drill, and screws to replace the broken set and fix this sh*t in the cold cuz if you don't you wont stop hearing how the garage door has to be manually opened and closed for the winter.

Installed it correctly and mounted the sensors into the wall so they wont be run over accidentally again.. unless he puts his car through the garage wall/posts.

Happy Wife ... Happy Life....

These sensors (801CB) didn't work for me. I accept responsibility for that because although the instructions state "The color of the PROGRAM BUTTON....is purple, orange or red, with a yellow indicator light" I thought maybe that was a typo. My Program Button is yellow and the indicator light is red. My garage door opener is a Sears Craftsman (Mdl: 139.53615SR - 1/2 HP). I believe I installed it around 1995 or before. I took a chance and ordered these because some reviews suggested that they might work. Before stringing the wires, I temporarily hooked everything up, made sure the lights on the sensors were illuminated (solid beam) then, while the door was closing, I stepped between the sensors to interrupt the beam, and the door continued to close - nothing happened.