It has a size of 1/2 X 13, H5, a thread series of UNC, and a trade name of YG Tap GP.118. 3 Fluted Spiral Pointed Plug Bright Finish Standard Tap It does not have coolant thru.This YG-1 TOOL CO brand 3 Fluted Spiral Pointed Plug Bright Finish Standard Tap is made of HSSE-V3 material and has a bright finish.