GR10q 4 Pin 16W 3500K Warm White Compact Fluorescent Bulb, CFL Save Square 4...
Item model number: GR10q 4 Pin 16W. 4-pin bulbs are not compatible with 2-pin fixtures or ballasts. Will not light up without a ballast (This bulb uses a 4-pin GR10q connector, not a 2-pin GR8 connector! ).