The Dormer Combination drill tap is available with a 30 degree spiral flute. The combination of a core hole drill and tap to produce a thread in one pass. This significantly reduces the time needed to produce the thread on site with the use of a hand held power tool. There is no need for a tap wrench or tool change. Steam tempered surface acts to retain the lubricant and provide smoother cutting. ISO Dormer standard
Spiral flute geometry
Semi bottoming tap chamfer
Right hand rotation and cutting
Thread form and metric coarse