Terrific set of precision gunsmithing screwdrivers. As you push down on the handle a spring-loaded insert in the blade twists to grip the slot of the screw. In a range of sizes and lengths - please see photos. Very slim and well- made blades on these things. Set comes in what looks like a military oiled-canvas wrap.

I have very rarely seen any others like this, and never a set. Thanks for looking!