Made of for durable and practical use. They can be applied to all lapel pin, tie tacks, citation bars, service bars and jewelry making, etc. Suitable for jewelry making and DIY handmade projects. Meet your different fixing using needs. Features -Color:Assorted Color -Material:Iron, rubber -Size:1.10X1.10X0.80cm/0.43X0.43X0.31in - Easy to use, no tools required: allows you to install and remove it easily, handy and convenient for use. - They are good supplies for making DIY crafts. The pin back is tight and not easy to fall off. - These clutch back can be applied to tie tacks, lapel pin, badges, service bars, and jewelry making, etc. - It can be applied to lapel pin, tie tacks, service bars, jewelry making, etc., perfect for diy making. - Good replacement for lost backs badges, name tags, etc., very practical and useful. Package list: 430 x pin backs