smart ForTwo 453 headlight dust covers for Novsight 22000LM LED bulbs

###Motivation I have halogen headlights in my smart ForTwo 453 and wanted something brighter. I decided to try LED ones. I could have sourced factory LED headlight assemblies for this car, but they are expensive, and the retrofit requires coding. Additionally, some drivers who had the halogen headlights and now have the factory LED headlights say that the factory LEDs are not significantly brighter than the halogen headlights. ###Searching for a solution Aftermarket LED it is then. The best LED bulbs I could find at a reasonable price are Novsight 22000LM H4 LED headlight bulbs. There are cheaper LED bulbs on the market, the problem is with the light pattern. The light emitting chips must be exactly where the halogen bulb's filament is supposed to be. The reason is that the headlight assembly, especially the reflector, is designed and tuned to maximize light output and beam shape for the H4 bulb, whose dimensions are standard. If the light source is off by a few mm, the light pattern will be wrong, and you will blind oncoming traffic. Many LED bulbs have this problem, but it seems that the Novsight 22000LM is well designed, the light pattern is very close to the original halogen bulb's, incoming cars do not flash me. It is also well made (solid aluminium body including the adapter ring, copper heat pipe). Yes, Novsight should pay me, but sadly, they don't. Guys, I could use a million dollars. Or a pair of H4 LED bulbs, from the Quick & Angry line. Family? One bulb? Not even one LED? Oh well. Fortunately, while these LEDs are much brighter than the factory halogen ones and they do heat up, the cooling is very good, so that the headlight assembly runs much cooler than with the halogen bulbs, while the lights are on, even for a longer period. The factory halogen high beam heats up the headlight to around 137°C max after a few minutes, the LED high beam only to about half of that. I measured both with a thermometer gun, from the front of the stationary car. While driving, the airflow will keep the headlight a little cooler. I did not measure either bulb's body, it is probably hotter. However, these - and most - LED headlight bulbs have a fan, to take away the heat generated by the LED chips, towards the back of the bulb. Unfortunately, the original halogen bulbs are protected with a watertight dust cover and the new LED bulbs are too long in the back, they do not fit under the dust cover. You need to change the dust cover. ###Backup solutions - You could make a hole in the dust cover, so that the LED's fan sticks out in the back. I find that a bad idea since you lose moisture protection. - You could use lower brightness LED bulbs (still brighter than halogen), which have the exact same size as the original halogen bulbs. The fan is integrated in the middle of the bulb's body, instead of sticking out in the back. One problem with that is that the fan keeps the heat inside the headlight housing, instead of taking it away. It will survive, although I've read reports that the reflective layer inside the headlight housing might get damaged. Novsight has some 1:1 LED H4 headlight bulbs like that. I also saw another model, but did not test them for light pattern: https://www.aliexpress.com/item/4000497767128.html - You could use the brightest halogen bulbs you can find (Philips +150% or OSRAM or others), but a good LED is brighter. - You could use a rubber insert specially designed for LED headlight bulb retrofits. However, I could not find one which fits. This does not fit either https://www.aliexpress.com/item/32915204487.html, because in the smart 453, there's not enough space around the bulb, unlike the video they show. - You could get a closed dust cover, like the factory cover, but deeper. However, this would enclose the LED's fan and it would be working in a hot environment, shortening its life. If you decide that it is an acceptable compromise and will not melt anything, you need the 80mm inner diameter dust cover, like these: https://www.aliexpress.com/item/4000415182734.html. Make sure that you get a pair (two dust covers). I did not try this solution, maybe it would not fit well (the original cover is oval, this is round). ###Chosen solution In the end, I decided to design and make my own dust covers, specifically for these LED bulbs. They can definitely be improved, but they work for me. The dust cover is made of two parts, printed separately: - the inner part, which goes on the LED bulb's body; - the outer cover, which goes over the inner part and the car's hole. ###Left-hand drive, right-hand drive Due to the curvature of the car's design, the inner part is different for the driver side and for the passenger side. The outer cover is not different for the two sides. I have a left-hand drive car, but I'm certain that right-hand drive cars (in the United Kingdom, Japan etc.) have the exact same headlights, probably adjusted differently. However the 12V battery seems to be on the other side for RHD cars, so.