1.Size:Alloy steel from 4 1/2" to 20" 2.Buckle:BTC,LTC,STC 3.Grade:k55,J55,N80,P110 4.Back -pressure: 35mpa above 1. Descriptions:Float collar&float shoe are essential accessories of casing string in cementing work,to guide casing string smoothly ,function as an one-way back pressure sealing valve ,with features of easyconnected ,sealing effectively and high temperature resistance.2. Features: 1) ...