Double Side Silicon is mainly for flies on which you do not want to damage the wings.
Double Side Silicone fly box consists of 4 models / sizes that have the same configuration. There is a silicone plate on each side that keeps the flies safe. Silicone has much better grip than slit foam, and since silicone has better grip, the plates can also be thinner and still hold the hook well. It provides better ceiling height and utilizes space more efficiently. These boxes are mainly suitable for dry flies and other bulky flies on which you do not want to squeeze the wings. Each side is opened separately and there is a sealing strip of silicone that ensures the drawers can withstand rain and wading without the water coming in and soaking the contents.
• Mini: 106mm length x 76mm width x 34mm thickness. (This article)
• Small: 125 mm length x 100 mm width x 42mm thickness.
• Medium: 155 mm length x 100 mm width x 44 mm thickness.
• Large: 186 mm length x 116 mm width x 40 mm thickness.