The more common of the two are the take-down versions. These are easily taken apart so the the barrel and slide assembly are removed from the frame. This makes them easier to pack into a short case. These were considered more delux than the cheaper solid frame models which were not as easily dis-assembled. Many cowboys prefer the solid frame because it is slightly shorter and usually lighter. But they are more rare. They used to be cheaper, but have become more expensive of the two.