evo.com | BCA Snow Study Tools > The BCA PC Crystal Card is a pocket-sized snow science lab with a crystal-clear surface to analyze snow grains and a built-in slope index to help determine angles straight from your topo map. Made from durable Lexan polycarbonate that doesn't absorb solar radiation like aluminum, this versatile tool gives you more time to study snow crystals in sunnier climates, taking your snow safety skills to a whole new level. 2mm Grid Material Lexan Polycarbonate Metric Ruler 6" x 4" / 15 cm x 10 cm Beveled Edge | BCA PC Crystal Card 2026 | Aluminum