For the commercial developer and other large projects or job sites requiring large amounts of signage posting and storage. Holds up to 30-inch plans with double the posting area for larger jobs. Leak-proof, all-weather high-density polyethylene (HDPE) construction, assembled by hand in the USA. Comes standard with a shatterproof polycarbonate window and thumb latch. Lasts job after job!Pre-drilled cover snaps securely shut with a deep overlap to back, protecting against weather and dirt while preserving access to contents inside. Generous posting area and interior storage for large rolled plans. Mounts on post or wall. Write on with a grease pencil; easy wipe-off with a light oil solvent for next job. Replacement decals and custom embossing available.Lifetime guarantee against defects.