Oak staircase: which oil for after-treatment?

Hello everyone,
I have an oak staircase (oiled at the factory).
Now I would like to oil it again from time to time.
QUESTION:
which oil (type + brand) have you used?
THANKS to you for the answer
Best regards

At that time, we received a bottle of oil (without label) from our stair builder, but you can actually use any wood oil from the hardware store. We chose Clou hard wax oil.

I would use Leinos or Osmo hard wax oil.

I am thinking of linseed oil (-varnish). I am afraid that hard wax will change the color. What is your experience?

It does neither more nor less than oil itself. The color changes when color pigments are added to the oil.

We oiled all our bathroom shelf plates over the weekend with PurSolid Hard Oil from Auro. It is normally for floors but should also work on stair steps. In general, you can probably use any oil, whether 100% natural or not.