Description:
Five piece set includes bits for drilling pilot holes for screw sizes #5, #6,#8,#10 and #12
Special designed steel counter sleeve countersinks or counter bores pilot hole
Adjustable counter sleeve depth with Allen wrench
Standard hex shank is quick change compatible
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

Specifications:
Color: As the pictures show
Material: HSS Drill 4241
Black chamfer drill body material: steel 45
Dimension:
5# 1.98mm(0.07795 inch)x 50mm(L)
6# 2.38mm (0.0937 inch) x 55mm(L)
8# 2.78mm (0.1094 inch) x 60mm(L)
10# 3.175mm (0.125 inch) x 63mm(L)
12# 3.56mm (0.14 inch) x 65mm(L)
Shank: 1/4 hex shank