When I bought my M1A many years ago I got extra parts with it. I just put them in a box and stored till last week. I have a winter safety and the winter trigger assembly. It's not the trigger you have to drill holes in your stock and fasten with screws. This one you lift up the trigger guard about 1/4 in. Then slide trigger assembly slot onto trigger guard then snap trigger guard in place. Takes about 30 seconds. Didn't find it in any of my M14 books or manuals but I did find it in my M1 Garand TM manual dated 17 March 1969. Manual says Winter Trigger Kit Type T-36. I have dry fired with it on, feels quite a bit different. Has anyone ever fired a rifle with a winter trigger? I'm going to try it in a couple of weeks when I can get to a range.