* Mr. Pen adjustable cardboard corner protectors come in a pack of 400, providing reliable protection for frames, artwork, and other fragile items during shipping or storage. * These corner protectors are designed to fit frames measuring 1", 1.5", and 2.1" thick, ensuring a snug and secure fit for various sizes. * Constructed from durable, high-quality cardboard, they offer excellent impact resistance, safeguarding your items from damage such as dents, scratches, and bending. * The easy-to-assemble design allows for quick application without the need for adhesives or tools, making them convenient to use when packing large quantities of items. * Ideal for moving, shipping, or storage, these corner protectors provide peace of mind, keeping your valuable frames and products safe from damage.