When I was a lad, it seems like every grown man (and a lot of women) I knew carried something like this in their pocket (or purse), and those tiny knives saw a lot of use in daily life. Even the farmers I knew, who almost universally carried a three blade stockman pattern with main (clip) blade of about 3 inches, always seemed to have one of these little patterns (called "go to meeting" knives due to their use on Sundays), which they carried whenever they came to town in good clothes for church, meeting with their banker, or dates. With the new TSA pocketknife rule relaxation almost upon us, I started looking at what I have and what would pass airport security. For sake of comparison, I put my Jess Horn lightweight pocket fighter in the middle. It has a 2.6 inch blade (and is a lock-back)--it wouldn't pass. Also for scale (and because this is a UL flyfishing forum) is a vintage Orvis CFO II (2.5 inch diameter). The aluminum handled SAK on the left is a "discontinued" Bantam, which is the most practical pattern I've ever had in my pocket for everyday use. Its blade is just a mm or so over the TSA limit, but the elegant pearl and nickel silver handled 1970's era Hen and Rooster (bottom left), which also sports a combination tool, passes easily.