Your very nice set is shown in the 1959/1960 catalog as a "twin set," with models P48A (the larger) and P28 (the smaller), with red, ivory or yellow "tenite" (celluloid) handles. These sets were also sold with bone or leather-stacked handles. Your set is considered to be a very desirable collectible. If you give it to me, I will tell all my friends that you are a very nice guy. Barring that unlikely scenario, if I were you, I would not use those knives. I would keep them in dark, airy, cool area to protect the celluloid, and lightly oil the steel. Knives in the same general pattern, but less collectible, can be had to use, at a very reasonable price. Not these!