Almost every cheese slicing machine that uses wires has its own proprietary wire. The wire for the Cheese-o-Matic (Kaas-O-Maat) does not fit the Hotel Block Cutter (Hotelbloksnijder), for example. You can find the correct wire by entering the name of the machine in the search bar in the webshop.
Some wires are available in two thicknesses, like the one for the Hotel Block Cutter. A thicker wire will not break as easily when used for harder cheeses. However, a thicker wire will provide more resistance, which makes working with it a little more difficult. This is especially true for machines with lots of wires, like the Cheese Blocker Pro or Hotel Block Cutter.