so in our office boardroom, there's 6 ceiling cans that are spec'd for BR30 bulbs and had incandescent 60W / 65W soft white bulbs in them. looking at those originals i noticed that i have extra room around the bulb - so i grabbed a ruler and it looked like i could fit the BR40 if i take out that black plastic baffle. well, they fit - WITH the baffle in place. because BR40 are also longer, i could do a straight swap and get WAY more brightness, and because they're LED they don't get that hot so that plastic baffle ring nicely keeps them in place, snug, and doesn't warm up. PERFECT!with a dimmer, we can either dim them down for a more comfortable meeting or discussion atmosphere, or have them full power for working on drawings, plans, doing notes, etc.definitely worth every penny!!!