Ten of the Snap-On, Craftsman or General knives. They fit and that is assured. But I am not sure they are making them any more so figure what you'll need for the long haul.
I also added a drop of SuperLube to the slide and it's as good as new not that it loses functionality with age. ///Rich
I was cleaning out an old toolbox and found a Snap-On GA-169 Utility Knife that was in there for many years.
I took out the blade and after a trip through the ultrasonic I tried fitting a new blade. This is where the story gets interesting.
Who knew, of course YOU did but who else, that...