That time of the year again

Twice a year the same procedure: the tyres of our cars need to be changed (D. and I, we both have summer and snow tyres, not the all-season ones).
At least we have them on rims, so we can do the change ourselves.
Because the weather finally went towards around zero temperatures we decided we do it today.
Well, I did it. D. helped me with getting her tyres out of and into the garage, and she pushed the jack lever once.
In order to prevent my knees to "suffer" I used an old cloth.

The black thing in my thumbnail is a kind of plug needed between the jack and my car. Some cars are special :(