Many think the #5 1/4 was a Stanley invention. Stanley was not the first to make a #5 1/4 bench plane. They did change its classification to a junior jack however.
In the 1910 Ohio Tools catalog, they list a #05 1/4. The difference here is the size. The Ohio tools version was slightly bigger than the #05, and slightly smaller then the #05 1/2.
They also list a #05 3/4. I haven’t found one of those yet.
The Ohio Tools #05 1/4 and the 05 1/4C was 14 inches long with a 2 1/8” cutter.
Stanley made their version from 1921 to 1983, but the C version ended in 1942. Patrick Leach (supertools.com) call the C model one of the rarest bench planes made. This was 11 1/2” with an1 3/4” blade.
Stanley marketed this plane for teaching kids in educational institutions. As such it often came with an aluminum tote.
And pay no attention to the aluminum knob, that is a shop made addition.
The Bedrock #605 1/4 was made from 1925 to 1942. I don’t believe a #605 1/4 C was ever made. It was the same size as the #5 1/4.
Stanley 4 square made one of these but interestingly enough, never gave it a number. It was known as the “Household Jack Plane” Same size as the #5 1/4. It was made from 1923-1930. The first cap was plain, then Beginning in 1924 it had a stippled cap, About 1929 the 4 square logo was made (ref: Antique and Collectible Stanley Tools: Guide to Identity and Value )
Sargent made their #411 from 1926-1947 with the C model ending in 1943. This was 11 1/2” with an1 3/4” blade just like the Stanley.
Sargent made their #711 from 1922-1947 with the C model ending in 1925. This was 11 1/2” with an 1 3/4” blade just like the Stanley. And like the Stanley, this is a fairly rare plane
A Shaw patent (Sargent single number series) or a #11 was never made.
Millers Falls #11. Made from 1929-1970.
Also See the Sargent #411 Story