These are the sheets that slide under the IPM Bottom Board to allow you to monitor mite fall. If you are making your own bottoms or just need replacements for the IPM Bottom Boards, this is what you need. Corrugated plastic sheet measures 22" x 14-1/2" for 10 frame hive. Coat with Vaseline to monitor your mite fall.
Please note: that these Corex Sheets are included when you buy a new IPM Bottom Board.