 This 6-shot, .357 Magnum revolver uses a unique interchangeable barrel system, including a 2.5" snubnose barrel along with 4", 6", 8", 10", 12", and 15", partial or fully lugged shrouds with choices of solid or ventilated ribs, plus removable and interchangeable front sights.The Model 15-2 could be ordered as "Pistol Pacs" with 4 (or more) barrel/shroud sets shipped inside a fiberglass briefcase with barrel changing tool and clearance gauges; however, most pistols were sold with only one barrel, with the buyers able to purchase other barrels later.All barrels and shrouds within a model series are compatible, thus a Model 15-2 frame from the 1970s may be equipped with a barrel from the 1990s and shroud made in 2016.