The Vevor blueprint clamps 12-pack is designed for organizing and storing blueprints, maps, posters, artwork, and other large documents. Made from heavy-duty aluminum alloy, each clamp uses a spring-loaded mechanism and locking knob to hold materials securely without slipping. These clamps are compatible with I-shaped racks, R-shaped racks, and wall mount racks sold separately. Each clamp supports up to 20 lbs or about 100 sheets, making them suitable for offices, construction sites, design studios, and home use.