Smith & Wesson K frame hammer block, blue $20.00 Part 78 on the exploded diagram. Used, excellent condition hammer block from a 19-4, K frame revolver. Will fit other models of K frame revolvers. Only 1 left in stock Smith & Wesson K frame hammer block, blue quantity Add to cart Category: Smith & Wesson Related products LPA Smith & Wesson M&P Fibre Optic Adjustable Sight Set. $195.00 Smith & Wesson K frame Extractor rod collar $10.00