In the third edition the product image makes the impression that they would fit perfectly to the supporting surface of the jack and sit there also fixed.
Unfortunately, this is not the case, the rubber pad is much greater and is only loosely without protection against slipping on the jack.
Since it is difficult to recognize under the car, whether now the rubber center is on the jack and the car centered on the rubber, it is easy for tipping the rubber pad when pumping up the car.
Apart from offering the rubber pad a relatively large area on which the car's weight can be distributed well.
But for the price you could definitely still a kind of adapter attribute (eg a rubber ring for insertion), which ensures at least that the disc is centered and firmly on the jack.
