1.Grade:J55, K55, N80-1, N80-Q, L80, C90, P110 2.We also supply permium thread products by customer's request 3.Size: tubing coupling from 1.9" to 4-1/2",Casing coupling fro4-1/2"to 13-3/8" 4.Type: NU, EU(tubing coupling), STC,LC,BTC(casing coupling). 5.Surface treatment: Whole phosphating, or inside phosphating and outside coating 6.Packing: By carton, wooden case, wooden pallet, or by requirements of customers