A Sun Lighting branded 20-watts CFL (compact fluorescent light). This is an earlier unit, likely from the late 90s or early 2000s. I'm not familiar with the brand. The packaging doesn't really instill any confidence in the product.

Testing the bulb revealed it to be a 10 watts Cool White/Daylight type bulb, which is about as far as it gets from a 20 watts Warm/Soft White bulb. I'm not sure if this was mislabeled, mispackaged, or just a scam. It claims to be instant start, but looks to be rapid start to me.

The bulb itself seems to be made well enough, there are vents for the heat to escape the ballast and the quality of light in regards to flicker is excellent, there's no detectable flicker to the eye.