This HP carbide bur is a large inverted cone. It is 6.6mm in diameter at its widest point. The head length is 7.0mm. All LeBlond HP carbide burs have a 2.35mm (3/32") shank and are 44.5mm (1 3/4") in length. These US made carbide burs are designed for fast, smooth cutting and extended life. Availability: Usually ships in 2-3 business days 6.6mm Inverted Cone HPC1400$8.00 Thank you for visiting A&M Instruments, Inc. Diamond Dental Burs. You will be pleased with the high quality of your dental burs and dental discs. All of our diamond and carbide cutting tools are made in the US, in Alpharetta, GA. Copyright® 2003-2011 A&M Instruments Inc 770-772-6404