Patent-pending tooth pattern helps keep the cut channel free of sawdust, resulting in a faster cut; Replaceable 13 inch blade (7900-1) made with the same SK4 high-carbon steel used in advanced knives and precision cutting tools; Blade's steel extends through the entire handle, helping you make the most powerful cuts; Hook helps keep blade in the cutting channel, minimizing time lost reinserting; Lightly textured elastomer grip helps reduce hand fatigue so you can cut longer