The Busch® 77B Cup shaped burs are great for rounding the end of wires and prong tips because of the cutting teeth which are on the inside of the concave shell. Also know as concave cutters. Features precision machined, uniformly spaced multiple teeth for accurate and smooth cutting. Made of tungsten vanadium steel for strength and durability. Use with a lubricant such as Gesswein Lube-Stik to facilitate cutting and prolong tool life.

The 3/32" shanks measure approximately 1.75" long. Maximum operating speed varies with bur size. Please consult with ANSI (American National Standards Institute) for speed recommendations.