This refill set (10 cards) is for "Astor Mental" ...
and is made by Astor.

The cards are identical size and thickness to the original cards,
and work quite well. They're delivered in a plastic leather-like
card pouch (#1)

On my Astor Mental, the original cards had Bicycle Rider backs.
The replacement cards have a diagonal crosshatch pattern.
Upon some reflection, I think I slightly prefer the new pattern
over the original back design.

I needed replacements because after some years, the original cards had yellowed slightly ... leaving a band of unyellowed area in the middle. This is because I kept the cards in the device, and apparently more light reached it in storage than I thought did.

--

1. I recommend keeping them in the pouch when not,
to avoid having them yellow.