Genie Garage Door Opener 18004B.S Capacitor 50 MFD 1/3hp Models Compatible with some of Genie 1/3 Horse Power Garage Door Openers. 50-60 Microfarad (MFD), 220 Volts AC (VAC), 60 Hertz (Hz). 61A2D220050NNGI 18004-B Capacitor Genie 50 MFD Original Genie Replacement Part. Genie Capacitor 18004B.S round motor start. Easy used.