The Model 637 is part of Smith & Wesson's Performance Center, a series of guns that originate from standard designs or are created from the ground up. From hand-cutting and fitting to fine tuning for precision, these firearms are top performers. Products from the Performance Center are the ultimate expression of old-world craftsmanship blended with modern technology. FeaturesFixed sightsBasketweave wood gripsAlloy frameMatte silver finishSingle/Double action