It is a Lutron Hi-Lume dimmable and a Sylvania Quicktronic. Both 277. The Sylvania is a magnetic type, and the Lutron is an electronic. The magnetic works fine because it is just a 277 to 600 VACrms step up transformer. It is just underpowered by about 37 volts. The electronic one, however, will not start because it's not getting the correct voltage. It is more sensitive to input voltage. It needs 277 volts ± a couple of volts.