The design of these innovative crime scene markers makes them the most convenient evidence markers available. Each marker features two 3.5” x 3” surfaces and a third horizontal surface featuring a distinctive 2.5” or 5.5” cut-out printed with a metric reference scale, creating a useful L-shaped reference scale that can be used to frame evidence and act as a useful photographic reference. The inclusion of a scale allows for perpendicular photo angle or wall photos. Each scale also includes a set of photo cross hairs to help correct parallax. Each tent also features 2 hinges which allow you to use the tent in 3 ways. 1) standard 6 cm scale tent 2) a 6 cm x 6 cm scale cut out tent and 3) a 6 cm x 1 cm L-scale cut out tent. Made of durable plastic and stackable for compact, easy storage. Low profile design resists wind.