They keep the stock wattage to prevent overheating, but they shine like 50 watts. Some people haven't had problems with 50w bulbs, but others have. Go to www.sylvania.com and you'll find all the specs and part numbers on there. I'm not sure of the numbers anymore. I got mine at Advanced Auto. They had to be ordered, though.

02 Nissan Altima 3.5 SE, FULLY LOADED Old car- 99 SE Sport ATX w/ SVT body kit (for sale...asking $4,200 OBO), nicely modded, high-flow exhaust y-pipe back and KKM. 95K, but 95% are interstate highway miles back and forth to college everyday.