Signet uses standard schedule 80 iron saddles for most of our Rotor-X installation fittings. These saddles will accommodate a range of pipe outer diameters. The chart below lists the minimum and maximum pipe dimensions for each Signet installation saddle. If you need to replace the plastic insert in any of these saddles, the part number is listed here. When ordering, specify the plastic insert part number AND specify the saddle part number where it will be used. This will ensure that you receive the insert with the proper threads.