5-40 Green Ring Spiral Point Plug DIN 371 Standard Tap, HSS-E (Cobalt), H3/H4, Steam Oxide Finish Type: Green Ring,Number of Flutes: 3,Hole Type :Through Hole 56mm Overall Length, 3.5mm Shank Diameter, 18mm Threading Depth, Without Coolant Through, Chamfer Form B: 3.5 to 5 Lead Threads Series No. 2881, Order Code 03.1750, Guhring Part #9028810031750