E-28A5 Smith-Blair 2" Standard Coupling for Steel Pipe Smith-Blair Standard Couplings for Steel Pipe are designed with push on gaskets. They are engineered to simplify installation and ensure a tight seal. The standard couplings can be used to connect IPS steel pipes with 1/2” thru 24” diameters.Nom Size: 2"Follower Dia: 4-5/8"Sleeve Thickness: .120Sleeve Length: 5"Bolts Dia: 1/2"Bolts Length: 7"