If your Reginox sink is equipped with the characteristic logo consisting of parallel lines and the inscription
REGINOX made in Holland near the overflow provision,
you should install this specific basket strainer.
Reginox R1181 - R1182 Basket StrainerThe technical identification characteristics are as follows:

REGINOX made in Holland at the overflow provision.
Upon inspection of the drain opening, it is visible that the drain hole is manufactured using the punching method. (there is no demarcation line visible that would indicate a separately screwed-in component.)

Punched drain opening without mounting rim
If the configuration of your sink matches the specifications above, you should install the mentioned basket strainer.