The Cose Rectangular Plastic Buckle, 30mm in red, reference 140215, is a rectangular frame-shaped plastic buckle used to adjust the length of straps and belts on backpacks, bags, and accessories. It does not have a fastening function, only a sliding mechanism. The red color makes the piece stand out, making it a popular choice for backpacks and accessories with a more vibrant style. It is a lighter and more economical alternative to metal buckles, while maintaining the same adjustment function.