Stan Musial bailed out on Bowman after their 1949 set and signed some exclusive deals that left him out of the mainstream sets they and Topps issued in 1950 and 1951. If you wanted a card of Stan the Man in 1951, you needed to find a retailer carrying the four different boxes housing Berk-Ross product. If you were lucky enough to do so, you found an oddly tinted horizontal pose of Musial inside box #2, featuring a really nice action shot of him playing First Base. The centering is pointed to the upper right on this PSA 6, which is the typical look for the set, and the card was separated a bit roughly, also a characteristic of Berk-Ross.  All else is in order though, on a card that's a surprise to some people who wondered where Stan wandered off to for 1951.