Serial Number Search, thru Ruger, shows this gun was produced in 2002 as a Ruger SSM-4F-S Model: 06515.
this is more commonly called a Baby Vaquero, w/ short grip frame and it is the Ruger "Color Case" which was a chemical application,,,,
fyi,,,, that does not hold up very well under use, wears off and dulls. A lot of them get Blued when re-done.
Here is some education & good pictures of this model.
Buy a RUGER & COMPANY INC 06515 Pre-owned & As NIB Sturm Ruger New Model Single-Six SA revolver in .32 H & R Magnum cal. Beautiful for sale by S Harris on GunsAmerica.com the best online marketplace for buying and selling semi auto pistols, firearms, accessories, and collectibles : 917171261
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