Owing to their position on the car and chrome on metal these must be cleaned weekly. They are a direct replacement for MK3 on original number plate lamps and are less the 2 light lens, which are the same fitting for this lamp. These lamps use M4 screws (LINK]MSB2003[/LINK] to retain the lens and will need drilling out slightly. There are 3 types of this housing on the market but this one is the best quality and has the best chrome finish of them all, hence slightly more expensive.