In my observation most Snap-On tools have a date code present. A chart is published which decodes the dates. There are exceptions, and I run into them. Most exceptions have a patent number marked, but there are again exceptions to that. But as a general rule you can rely Snap-On tools providing the simplest/easiest dating of all, IMO.
There is also a nice website that focuses on collecting Snap-On tools;
http://www.collectingsnapon.com Lots of reference material for Snap-On and BluePoint brands. Although I've not seen it stated, I believe the website's owner may be a member here.
