Grundfos 539605 Threaded Cast Iron Flange Set is compatible with Grundfos UPS/TP 32-160 and 40-ALLL Circulator Pump models. This kit includes (2) flanges, (2) gaskets and (4) bolts and nuts. Features NPT end connections and a 1-1/2 fitting size. Constructed of durable cast iron material. Check manufacturer recommendations to ensure a proper fit.