QUANTITY: With 30 round carabiners, shiny silver luster, electroplated with environmentally friendly materials. The inside diameter is 38 mm, the diameter 45 mm and the thickness 4 mm. .ROBUST MATERIALS: These spring rings are made of zinc alloy, which is rust and corrosion resistant, lightweight, durable and strong. Smooth surface and edges make them safe to use without scratching your hands or things. .Multi-function: This round loop is versatile, you can use it to extend a bag strap, use it as a key ring or carabiner, hang various clipboards, or make your own by hand, etc. In short, you can use it in any condition you think. .CONVENIENT AND PRACTICAL: Delicate design with ample spring retention makes the carabiner hooks flexible enough to stretch back to their original size and shape. Exquisite design with built-in spring allows the snap clips to open and close smoothly, so as to ensure secure fixing and convenient use. .Easy to use: The spring alloy buckle open button has high sensitivity. You can easily use it to join things firmly. But please note that it can support a weight of up to 5 kg and is not suitable for hanging too heavy objects. .