The Stanley fixed blade utility knife is designed for heavy duty cutting. It is made with super duty cast steel for durability and features a nose overlap at the top and bottom of the handle for added strength. Positive fixed blade retentionExtra heavy duty textured aluminum handleAccepts all Stanley utility knife replacement blades3 blades and steel blade guard in handleReplacement blades 11-911 (2512-3308) or 11-921 (2512-3357)