This was a request from some random person on the internet. They wanted a cherry mx keycap that would span two switches on a standard keyboard. On their keyboard, they had a split backspace, and they wanted just a regular 2u backspace key. They referred to it as a Point-of-sale keycap.

NOTE: this will not fit a standard backspace with a single switch and stabilizers. It is designed to fit over two normally space switches.

There are two models. The model POS_2u_Cherry_row1_tinedsupport.stl is designed to be printed curvy side up on an FDM printer. The tines are adhesion helpers for the stems. After the keycap is printed cut these off with a flush cutter. If printing on an FDM printer, there might be some trimming, filing, or sanding required to get the keycap to fit well. To get a nice curve on the top print at .1 layer height.

The POS_2u_Cherry_row1.stl is the keycap with no pre-made supports. This one is best done on a resin printer, or an SLA printer. For FDM, you could make your own adhesion helper (such as a brim) or if you don't mind sanding the curved top, print this one upside down to get a good stem fit.

These keycaps were made using this library:
https://github.com/rsheldiii/KeyV2

My keys.scad file looks like this:

For details on the different functions refer to the documentation for the KeyV2 library link above.