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They do look like they might fit a K-frame square-butt revolver, but the only way to know for sure is to install (or try to install) them on a weapon. I can tell you this: if they fit a K-frame, there should be a half-round cut near the top of each grip (to center and secure it on the upper portion of the grip frame), and a small (about one-eighth inch?) blind hole (not the mounting screw hole) on each grip near the center of the bottom edge (for a roll pin that sticks out on both side of the frame, used to "locate" the bottom of the grip correctly).
Originally Posted by zembrey
"Placement is power" -- seen in an article by Stephen A. Camp
(RIP, Mr. Camp; you will be remembered, and missed)