GLQEX-PVTCL Beekeeping Queen Excluder Trapping Grid Net Tool - Plastic Vertical - 19-1/4" X 10-1/4" X 1/2"

See my other comment about timing frames. Betterbee has a frame isolation cage. I haven't used it. Bob Binnie has a video showing how he sets up timing frames with two queen excluders made from luan and a plastic excluder. https://www.youtube.com/watch?v=0iV7Q__s8SkI found the vertical excluder on Amazon. It doesn't actually fit the box length very well, it needs trimming and sanding (use dust collection) to fit. A queen can be isolated to a smaller area with a push in cage. There are many ways.