They are Energy Star certified, and UL listed for damp location installation and contain no mercury or other harmful chemicals.. Upgrade to LED with these standard A19 shape household light bulbs with a GU24 twist and lock base. LED GU24 Twist and Lock Base Dimmable 90 CRI Energy Star A19 Light Bulb, 2700K, 6PK These bulbs are Title 20 certified, they meet California's Title 20 criteria At 10 watts, they use less energy while providing as much light as a traditional 60 watts bulb at a 800-lumen output and have 90 CRI.