Reducing Bushing, Size: 3-1/2 X 3 IN, Material: Aluminum, Finish: Natural, Connection: NPT, Standard: Class I: Groups A, B, C, D, Class II: Groups E, F, G, Class III, UL 886 (1203), UL E10444, CSA C22.2 No. 25, C22.2 No. 30, CSA 065181