I want to build an automatic chicken coop door opener so that my girls can get out and get their day started before I do. I searched under automatic door opener on this website and found the info about the Door Opener system that "Nifty-Chicken" built using a car lock actuator and other parts. However I was unable to easily locate said car lock actuator, while on the other hand, doing google searches under automatic chicken coop door opener, I found a motor that seems to be made just for chicken coop automatic doors. It's the Add-A-Motor D20 (model D20) and it's what you'd use for the plans featu red at this website: http://www.buildeazy.com/photo-chicken-coop-beatarticle.html. The author of that article was using the Add-A-Motor 80 (Model 80) but the Add-A-Motor company states that they don't recommend that model be used for this purpose, but use the D20 model instead. I ordered one of those today and hope to be automating my coop door next week, so my girls won't spend an hour yakking from 6am to 7am bothering the neighbors while complaining that I haven't gotten out of bed to let them out yet.