TEMO 5pc 5/16 Inch Diamond Coated Drill Twist Bit for Glass Marble
New 5 pieces of diameter 5/16" inch (8mm) diamond coated twist drill bits. The total length is 4-1/4" (110mm) long and working length is 3-1/8" (80mm). ALL working length is diamond coated, more long lasting. Suitable for glass, marble, tile or rock. Please add some water when drill a hole.