Specifications: Four piece set includes bits for drilling holes for screw sizes 3mm, 4mm, 5mm, 6mm. Special designed steel counter sleeve countersinks or counter bores pilot hole. Adjustable counter sleeve depth with wrench. Drill and countersink for wood screws without changing bits. Drilling length can be adjusted for various length screws simply by loosening and tightening the setscrew. Item Name: Countersink Drill Bit Set Material: High Speed Steel Quantity: 1 Set/5Pcs Features: Woodworking Tool, Portable, Durable Size(Dia x L) 3mm x 60mm/0.12" x 2.36" (Approx.) 4mm x 75mm/0.16" x 2.95" (Approx.) 5mm x 85mm/0.20" x 3.35" (Approx.) 6mm x 93mm/0.24" x 3.66" (Approx.) Notes: Due to the light and screen setting difference, the items color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 4 x Countersink Drill Bit 1 x 1/4 He-x Shank