Addo X calculator, price?

From: kcz@kringloopcentrumzeist.nl
Email: Kcz@kringloopcentrumzeist.nl


Hello, recently someone brought an " addo x" calculator to our second hand store here in the Netherlands. We are trying to find some information on the price, but so far no luck yet. Maybe anyone can advice us a little? I would appreciate any help. I will try to make a digital photo of it for clearity.