StoreSMART - Magnetic-Back Rigid Protectors 5-Pack - 4" x 6" - Clear Plastic Sign Holders - Refrigerator or Locker Magnet - Top Loaders - HPP4X6M-5 Made of clear, high-impact 16 mil PVC vinyl with a 40 mil opening. Overall size: 4 7/16" x 6 1/4" Inside capacity: 4" x 6" Open on the short or long. Has one strong 1/2" x 4 3/4" magnetic strip on the back.