Kreg Pocket Hole Screws

Fine thread screw suits hardwood i.e. oak, maple, walnut, cherry etc. The coarse-thread screw has a larger thread diameter and provides greater holding power for plywood, MDF, melamine and pine.

Washer Head style is the most popular as it provides the largest amount of surface area to seat firmly in the bottom of the pocket, especially for plywood or pine. The large washer head assures that the screw is not overdriven in the bottom of the pocket.
The Pan Head style is slightly smaller in both the head and shank diameter than the washer head screw and is a good alternative to the washer head screw if both work pieces are hard woods. The Pan Head style is also of benefit in the 1" length as it allows one to join 1/2" material to 1/2" material and easily seat the screw head below flush.