The Nos. 400 and 401 were Atkins' finest saws, and the only ones made with rosewood handles. They had more taper grind and more polished blades than Atkins' next-best saws. The Nos. 400 and 401 were priced 63% higher in 1937 than the mid-priced Nos. 51 and 53. No other Atkins saws had tropical wood handles. 1950 is last year for which I found Atkins No. 400 advertisements.
Atkins' finest saws, the No. 400 and No. 401, in 1937