ROBERTSON 2P20010 RSW240T12120 /B Quik-Pak of 10 Fluorescent eBallasts for 2 F40T12 Linear Lamps, Preheat Rapid Start, 120Vac, 50-60Hz, Normal Ballast Factor, NPF. (Item succeeded by Robertson 2P20132, Model RSW234T12120 /A) Item succeeded by Robertson 2P20132, Model RSW234T12120 /A Also offered as a single packaged version with Robertson successor item 3P20132 RSW234T12120 /A Equivalent to: Philips Advance REL2S40SC, Osram-Sylvania QTP2X40T12120RSNSC, Universal B240R120HP Equivalent to:Fulham WHCG9127T12RS, Keystone KTEB-240-1-TP, General Electric GE 97499,GE240RS120-DIY Two Year Factory Warranty-ONLY if the Amazon Seller is ROBERTSON WORLDWIDE.