When I fitted these to my Leon the rear top brakelight (in rear window) constantly glowed with sidelights on. It looked quite good, still went brighter when brakes were applied. I removed them as i had done the same to the other car,
ibiza mk3 sport tdi, and had warning lights on and all sorts of electrical problems due to the bulbs, they use less power so the car thinks there is a fault. This was only the
ibiza mind, but I took em out of the leon just to be onthe safe side as it cost me alot to figure out what was causing the faults on the
ibiza. Apparently some people have used resistors to cure the voltage difference. I think you have to use red for red bulbs, can`t remember to be sure though............