Feit Electric 13-Watt Equivalent PL Twintube CFLNI Bi-Pin Plug-In GX23 Base CFL Replacement LED Light Bulb, Cool White 4100K (1-Bulb) BPPL13/841/LEDG2HDRP - The Home Depot
Feit Electric 13-Watt Equivalent PL CFLNI Quad Tube 2-Pin GX23-2 Base Compact Fluorescent CFL Light Bulb, Soft White 2700K (1-Bulb) BPPLD13/HDRP - The Home Depot
Technical Precision 13W Compact Fluorescent T4 CFL Bulb Replacement for Panasonic FQ13E41U/2 Light Bulb 2 Pin GX23 Base Quad Tube - 3500K Natural White - 2 Pack - Amazon.com
18 Watt 2-Pin Double Twin Tube 835 Color Temperature Plugin CFL Lamp