This item is manufactured with premium plastic for and use. It is great for variety of uses such as loose-leaf, memo filing and sample holders. These rings are two holes to fix in, not like other metal rings, without any strength they can be easily install. Will not hurt your hands or children's hands. Features - Color: Pink, blue and purple. - Material: Plastic. - Size: 3.50x3.50x0.30cm/1.38x1.38x0.12inch. - These discbound expansion discs are made of plastic material, lightweight, and not easy to break, the surface is smooth to ensure that the page does not get stuck when turning. - Plastic binding rings can be easy and convenient to to add, remove and replace notebook pages, without damaging the paper. - At the same time, bright colors can attract children's or students' attention and make them happy to DIY their own projects. - You will get 30 pieces binding discs in bright colors, meet your multiple needs and help you do document classification. - Great for fastening pretty document stack, index, cards, papers and keys, make them organized and not messy. Package list: 20 x pink binder rings 20 x blue binder rings 20 x purple binder rings