Brighter than 40w they replaced with frosted bulb they spread widely. Slightly warm when they remained lit long. Immediate ignition and extinction. It remains to see their life! Edit: after 3 days of use (10 bulbs distributed between living room and kitchen), one of these bulbs is already HS! The plastic base that was really just warm heated ... We'll see in a week if I have to further decrease the note ... Edit2: 4 months after purchase, I now have 3 HS and 4th sizzles! I would not recommend the outright!