Fluorescent to LED Troffer Retrofit Kit comes in 2 x 2 ft model.

Available in 3,500K, 4,000K, or 5,000K color temperatures, Litetronics

[source: http://news.thomasnet.com/fullstory/Fluorescent-to-LED-Troffer-Retrofit-Kit-comes-in-2-x-2-ft-model-20040783]