97636 - F42TBX/841/A/ECO - 42 Watt Triple-Tube Compact Fluorescent Light Bulb, 4100K

Fit perfectly

Takes a minute to warm up but it works fine.

Worked fine but.. then I found the ballast wet the bed ($$$) so I scrapped this plan and adjusted my lamp to use common CFL screw-in. This bulb is a more 'round' shape but the lamp has a good reflector so I still get good light for reading! This is what I did: I bought a 1 dollar adapter and wired it into my expensive (and old) floor lamp. I bought a six pack of relatively cheap & efficient CFL bulbs (with a typical Edison screw-in base E27, 27 millimetres in diameter). If I want more brightness or a different Kelvin color I can swap it in cheaply. My wife loves the Whiter light for reading!

I wanted a brighter bulb to replace my 26 watt cfl, so I ordered this 42 watt bulb. I found out that the design of the 26 watt socket includes two plastic tabs that prevent inserting the 42 watt bulb. As I didn't know if that is because the 42 watt bulb would overload the ballast, I did not break off the tabs, but asked Amazon to accept a return for my mistake. Amazon bailed me out and gave me a refund (they paid for my education on this).

Cannot find these anywhere locally. Fits perfectly in my Broan bathroom fan/light. Be aware these bulbs do take a bit to reach full brightness. Sometimes they start relatively bright and other times quite dim. This is an issue I have found that is common to this bulb design. I have tried several brands in the last few years and they all have the same issue. These GE bulbs are the "daylight" color and work well in a bathroom. This is my second time buying a GE bulb of this type and they have a pretty good life span. Beware of cheaper no name bulbs. I have found they usually have a shorter life.