YG-1 F4 Series Vanadium Alloy HSS Spiral Flute Tap， Steam Oxide， Round Shank with Square End， Bottoming Chamfer， 1/4"-20 Thread Size， H3 Tolerance<img src="http://ecx.images-amazon.com/images/I/41LofwXwbWL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/31OBnnMJrZL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/51s6dbUQThL.jpg" noproxy>