To answer your other remark:
And here I thought it was mechanical :-/.
See how the slider shaft is part of the same plastic moulding as the plastic plate under the keycaps? That's a good sign that it's not mechanical: it means that the plate/case only exists to support sliders over the membrane sheets (typically with rubber domes between the sliders and membranes). Mechanical switches are typically discrete, i.e. you'll see physical switches soldered to onto a PCB, or mounted in stamped-out holes in a metal plate (though the plate is in rare cases also moulded plastic). Look at your own avatar: you can see the gaps between the plate and the switch module.
