This is a Drag Bit, specifically a 3-Wing Step Type Drag Bit (also labeled as a "Clay bit").
Type: 3-Wing Step Drag Bit (Blade Bit)
Size: 9 7/8 inches (251 mm) diameter.
Connection: 3 1/2 inch API Regular Pin (threaded connection to attach to the drill string).
Application: Primarily designed for drilling in soft to medium-soft geological formations such as:
Clay
Loam
Silt
Soft soil with moisture
Construction: Typically made of alloy steel with Tungsten Carbide cutting tips/inserts on the blades for durability. The "Step Type" design provides a fast and aggressive penetration rate in soft formations. It's commonly used for water well drilling, environmental drilling, geotechnical investigation, and shallow exploration.