These brooch pin backs are made of plastic material, small in size, lightweight and durable for long time use. The brooch locking pin back is applicable to uniform, badges, name tags, brooch, tie tack lapel. Also can be used for jewelry making and DIY craft projects. Features - Color: Black -Material:Plastic - Size: 1.60X1.60X0.90cm/0.63X0.63X0.35in -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., which is perfect for crafts making. -Good replacement for lost backs badges, name tags, etc., very practical and convenient to use. Package list: 400 x Pin Backs