*Concentric end mill extending 25 mm with concentricity at 0.02mm
*Spring collet with two ends cutting fine flute, not easy to made cutter loosen
*Interior deviced with upper contracting to keep cutter never be contracted
*Enclosed one Spanner and Plastic case or wooden case for every set
*The body Screw is Ground.
*Push inward the steel ball inside of screw nut and firmly strong valid vibration - absorbent power