The new Series TBV plastic ball valves from Dwyer Instruments Inc. are designed for medium duty industrial and commercial applications. The true union design allows for easy removal from a piping system without breaking down piping connections. Because of their all-plastic construction, these ball valves will never rust or corrode, and they can survive corrosive environments without the need for painting or expensive epoxy coatings. Units come in PVC plastic bodies with EPDM seals and are available in 21/2 to 4in sizes, featuring a full-port design.