If it doesn't say anywhere on it, can you post a pic? I'm sure we could help you figure it out.
Wait...do you have HID's? It should still tell you on the capsule what it is, but now I'm just wondering what you're running if they aren't stock. Also, it may not tell you what Kelvin they are, which might be what you're looking for. If it's HID, it's best to replace both at once anyway if you're trying to color-match as they lose some of their color over time.