United Abrasives- SAIT 45111 Tungsten Carbide Die Grinder Bur SB1 Double Cut/Alternate Cut 1/4" x 5/8" x 1/4" Tungsten Carbide construcion for long life and durability High Quality Manufacturing method delivers vibratin free operation Precision ground with diamond wheels to produce a very sharp uniform cutting edge Each enclosed in individual plastic capsules for storage and protection Excellent for confined or hard to reach areas