The Plastic Expansion Bead is only available boxes of forty. It is also known as the Plastic Movement Bead. This product is used in order to compensate for movement in plaster to prevent cracking. It is also used in situations that must allow for thermal movement. It is available in different widths, depending on your needs. The Plastic Expansion Bead is easy to use and can be easily cut to your desired size. For any more information or guidance using this product or any on our site, please speak to a member of our expert sales team today..