ROBERTSON 3P10008 BLU0100A04900 mHID Ballast Reactor Kit for 100 Watt S54, High Pressure Sodium Lamps, 120Vac, 60Hz, NPF (Item sold now as single quantities as ROBERTSON 3P10059, Item now available in a 4 ea. Quik-Pak as ROBERTSON 2P10059) Equivalent to: PHILIPS-ADVANCE 71A8007, OSRAM SYLVANIA LU100/120R, UNIVERSAL 123310U001 Equivalent to: HATCH GS100ARNAK, KEYSTONE HPS-100R-1 Save 32% and order the Quik-Pak of 10 individually packaged units: 2P10008 BLU0100A04900 Two Year Factory Warranty-ONLY if the Amazon Seller is ROBERTSON Worldwide. Take advantage of ROBERTSON's 60 years of electronic design and quality manufacturing experience