01M555 - Walter SST+ 55/64" Cobalt Prentice Drill Bit with 1/2" Shank

Heavy-Duty Drilling with Walter SST+ Prentice Bits

The Walter 01M555 55/64" SST+ Prentice Drill is a high-performance cutting tool designed to bring the capability of large-diameter drilling to standard portable power tools. Engineered for industrial maintenance, repair, and operations (MRO), this drill bit bridges the gap between stationary machining precision and on-site portability. The "Prentice" style design features a reduced 1/2-inch shank, allowing operators to utilize a 55/64-inch cutting diameter in standard 1/2-inch chucks found on hand drills and magnetic base units.

Durability is at the core of the SST+ series. Manufactured from a specialized cobalt blend, this bit is built to withstand the intense heat generated when drilling through hard materials like stainless steel and structural alloys. The inclusion of cobalt significantly extends the service life of the tool compared to standard high-speed steel, making it a cost-effective choice for high-volume shops. Furthermore, the bit features a special bronze SST surface treatment that acts as a lubricant, reducing friction and facilitating smooth chip flow to prevent overheating.

Operational efficiency is enhanced by Walter's exclusive point geometry. The self-centering tip bites into the material immediately upon contact, eliminating the common issue of "walking" and removing the need for time-consuming pre-drilling or center punching. To ensure maximum torque transfer, the shank is machined with three flats. This design feature locks the bit securely into the chuck jaws, preventing the bit from spinning under load—a common frustration with round-shank large-diameter bits. Whether working on mild steel, non-ferrous metals, or tough stainless grades, the Walter 01M555 delivers reliable, precise holes every time.