Star-M’s Extra Long Power Auger Bits are designed for deep, accurate boring in both green and seasoned wood - ideal for timber framing and log building.

Available in two extended lengths (400mm and 600mm) and diameters from 10mm to 22mm, these bits are excellent for creating through-holes in large or multiple timbers, or for reaching deeper than standard auger bits allow.

Star-M’s advanced manufacturing techniques, rigorous quality checks and use of premium materials ensure that each drill bit excels in five key areas:

1. Accuracy
2. Cutting speed
3. Runout prevention
4. Cutting resistance
5. Durability

• A burr-free lead screw for smooth, accurate starts
• Single spur for minimum resistance whilst making clean and accurate cuts
• Hand finished cutting edge
• An open spiral flute for fast chip ejection, especially during deep boring
• A hexagonal shank for a secure grip in your drill
• High carbon steel 53 HRC
• Easily sharpened with file 
• Made from high-carbon steel and manufactured in Japan with Star-M’s renowned precision and reliability.

See the sizing table for full specifications.

No.4 - 400mm:

No.6 - 600mm:

About Star-M:
Founded in Japan in 1923, Star-M has become a leading manufacturer of high-quality drill bits and woodworking accessories. Known for their precision engineering and long-lasting performance, Star-M tools are trusted by craftspeople around the world – from cabinetmakers and carpenters to green woodworkers and chairmakers.