The Dot Line Mini Digital Color Balance Cards are designed for the photographer who wants Color Balance Cards that can be used easily for small product photography or are readily available via a quick release lanyard. They measure 2-1/4 x 3-1/2". They are made of a laminated plastic that is resistant to moisture so they won't warp. This enables them to be washed with regular soap and water if they become soiled. The are flexible, 2-sided and more durable than standard cardboard cards. The lanyard comes with one each white, gray and black cards and features a quick release.