Series 29 and 129Y steam traps retain all the essential benefits of disc trap performance – they are compact, easy to install, self-draining and unaffected by water hammer or freezing, while providing the economy of integral seat design. Constructed of all stainless steel, the trap has only three parts; disc, body and bonnet. Simplification, made possible by incorporating the trap seat in the body, results in lowest possible cost per unit for this non-repairable steam trap.