I have them on a 8 foot door. They stretch out to 71 inches with the door closed seem to work just fine. I do have a safety cable passing through the springs.
These replaced my older sensors and worked great. Easy installation but the lights are upside down if you use the same brackets. I used some velcro and it worked great and the lights are on top just like my old ones.
Great price for 2 replacement battery for Liftmaster based on my search. Looks like the price went down after purchase too. Average time shipping due to postal service and batteries were labeled with a manufacturing date of this year.