The product does what it promises. In my Opel Astra K 1.6 CDTI, which was installed as a preventive measure, the regenerations now occur over a larger mileage range.

I used it because I drive short distances in the city. I don't have a gauge, so I installed it with the vag app. I immediately noticed an increase in temperature and a decrease in the percentage for regeneration, reducing particles. It worked instantly. I give it 4 stars because I haven't tested it for a long period of time.