Sometimes you're never sure if the key you get with the set is the one that was sold with it originally or not. The ones pictured here I'm pretty confident of. The 3 hole version in the lower left is the oldest, it's from a 1902 or 1903 set and came with a first series No. 11. The three to the right on the lower row are all from wind ups sold between 1906 to 1915. The two large keys shown upper left are from the early 1920s and came with the IVES line of boats. 2nd from the right on the top row is from a 1929 0 gauge windup with an American Flyer mechanism, The red key in the upper right corner was used with all the 1930 windups. Check the 1 gauge section for 1 gauge windup keys, they're entirely different.