Use 75% less Energy by replacing your 100 watts light bulbs with Feit Electric Ecobulb 4-Pack Mini CFL Twist Light Bulb. The light bulbs have a light output of 1600 Lumens and 8,000 lifespan hours. The four-pack Feit Electric light bulbs come packaged in a 10" x 5.50" x 2.50" box.