Description:  7pcs HSS 5 Flute Countersink Drill Bit Set Reamer Woodworking 3-10mm Chamfer Drill Bits.  Single Flute edge chamfer 90 Degree.  Heat treated & tempered high-carbon steel.  Use on steel, aluminum & other metals, plastic or wood.  Enlarge or countersink holes, deburr edges.     Specification:  Product name: Countersink drill bit set.  Material: High Speed Steel.  Color: Silver and black.  Chamfer Angle: 90 Degree.     Dimension:  3mm(Dia) x 60mm(L).  4mm(Dia)x 75mm(L).  5mm(Dia) x 85mm(L).  6mm(Dia)x 93mm(L).  7mm(Dia) x 10mm(L).  8mm(Dia)x 11mm(L).  10mm(Dia) x 12mm(L).     Features:  1. Special designed steel counter sleeve countersinks or counter bores guide hole.  2. Adjustable counter sleeve depth with wrench.  3. Drill and countersink for wood screws without changing.  4. Drilling length can be adjusted for various length screws simply by loosening and tightening the setscrew.  5. It is suitable for drilling machines with chuck, for drilling on hard wood or wooden floor.     Package Included:  7x Woodworking chamfer drill bits.  1x L-wrench