Material: aluminum, solid plastic, bakelite. Please understand before purchasing: determine the size you need. 1. Is it the standard corrugated box in the picture; 2. Determine the length*width*height of the corrugated box after folding. Suppose you have two types of airplane boxes: 32*23*8mm and 43*15*4mm. The maximum length is 43mm and the maximum width is 23mm. Please choose a clamp specification with a length of ≤45mm and a width of ≤25mm, and all will be compatible. This clamp is designed for secure holding of small boxes and packaging materials. Its durable construction ensures long-lasting use. Perfect for shipping, storage, and organizing tasks. Lightweight yet sturdy, it is easy to handle and adjust. Suitable for various applications requiring precise clamping. Ensure compatibility by checking your box dimensions against the specified ranges.