D4S: Osram 66440 CBB (7000K) (Duobox)
Best of the Best: Osram's CBI and CBH bulbs are top performers in their category, with an amazing amount of white bright paired with max luminosity; they're topped only by the Osram CBB (Cool Blue Boost) AKA the cream of Osram's crop. Brightest: In a recent comparison test, the Osram Cool Blue Boost bested the CBH, CBI, and standard by a solid margin. Forget about the fancy names and Kelvin ratings Osram is assigning, these things are simply the best & brightest bulb that Osram currently makes for use in your D2S headlight! (CBB = 460 Lux, CBH = 415 Lux, CBI = 340 Lux, Standard = 315 Lux). 7000K? So Osram rates these bulbs at 7000K, which is actually quite blue... But in our own testing, we found the CBB to have no more "blue" color to it compared to the CBH (which they rate at 6000K) and/or the CBI (which they rate at 5500K) - in this case, it seems that Osram is actually playing into the common misnomer that Kelvin rating = brightness by rating the bulbs accordingly higher. Weird! Backed: Bottom line? Though the CBB is new and yet to be tested by the masses, the popularity of their siblings (CBI and CBH) indicates to us that these are going to be extremely popular given the fact that they're considerably brighter, and only marginally more expensive than the alternatives. If you're looking for the best set of D4S headlight bulbs and aren't afraid to spend a few more bucks to get it, look no further, folks. Genuine: We are proud to offer these bulbs in their original retail packaging from Osram. We pride ourselves on being one of the last few distributors shipping genuine Philips & Osram lamps in the US. It is estimated that 80% of these bulbs sold through outlets such as eBay or Amazon are fakes.