Made of wood. Smooth and light, very strong and not easy to break. You can use them to hold your favorite photos, postcards, or use them to leave messages. They will make your life very convenient. It is usually used for photos, note, and leaving messages for your family. Suitable for many scenes, daily life, wedding, party, coffee store, etc. Features -Color:Assorted Color -Material:Wood -Size:4.50X4.20X1.00cm/1.77X1.65X0.39in - There are blackboards on these clamps, very creative and impressive. Mini blackboard can be written or drawn directly with chalks. - You can use them to hold your favorite photos or postcards, you can watch them at anytime. - It allows you to leave messages to your friends and family, making your life more convenient. - Can also serve as ornament and will not take too much space, delicate and creative look design. - Perfect for home, office, school, and more. Compact size, can be placed on any desk or table. Package list: 20 x blackboard wooden clamps