The picture is rather small, but it may be something like this video where you need two to join cutting mats to make one large one.
Joining cutting mats
I think the picture can be enlarged, at least I can, but this is an acrylic piece 2”x10-1/2” with suction cups on each end and a 2-1/2” slot in the middle in one side.
Last edited by Charle; 11-09-2022 at 04:44 PM.
Reason: Add better picture