Was just reading the Owner's manual and on Pages 3 & 4 they clearly mention a slot for putting a SIM card.
Page 3 shows the slot on the left side, and page 4 calls that slot, and I quote,(copy and paste are disallowed from the PDF):

3. SIM Card slot (on selected model) {sic}
The SIM card compartment allows insertion of a mobile SIM card for
3G functions.

It then tells how to eject with a paperclip.

Here's a link to the owner's manual:

Interesting ...! Let the games begin! Wonder if it's present on the motherboard in the shipping model. I own a Dremel .... LOL!