They were fitted in my Cupra when I got it. Worked as a normal glow plug do. I changed them when they failed and started breaking down for BERU ones as they are one of the types used from the factory. Seat use either BOSCH or BERU glow plugs. I checked with SEAT UK when I did it as I had issues with BOSCH ones supplied by SEAT. They were too ong by 5mm. The BERU ones are GN855 part number I believe.