This is a 50-pack of 2.38 x 4.1" Clear Rigid Plastic Vertical 2-Sided Multi-Card Holders from BRADY PEOPLE ID, designed to hold IDs on both sides. The rugged holders can display one 30 mil card on the front side and two 30 mil cards on the back, or alternatively a total of six business cards. They feature a clip bar for secure fastening, and slot and chain holes allow for easy attachment to any badge reel, lanyard, or chain.