Hi-Tech Diamond ball-shaped diamond burs are perfect for carving, grinding and pre-forming both hard and soft material such as glass, stones, ceramics, bone and metals. Each bur has a 1-1/2" long mandrel shank that's 3/32" in diameter and conveniently fits into a Foredom, Dremel with 3/32″ collet or any flex shaft hand piece that accepts 3/32 ...