1.OD:2 3/8"-6 5/8" 2.Grade:E,X,G,S 3.Upset:IU,EU,IEU 4.HB:Arnco100XT,150XT, ... . All threads are machined by CNC Lathes and inspected with API Spec standard thread gauges. To improve the galling ... roots are cold rolled. The products shall be equipped with pressed steel or plastic steel thread protectors on the ... produced in accordance to Standards of API 5DP, API7 &7-1, NS-1. RUSSIA RTN, RUSSIA GOST-R, ...