| There are four basic types of coverstock classifications in the BBI websites. They are: Reactive, Particle, Urethane and Polyester.
Reactive - First released in 1991, Reactive coverstocks are the most common material used. Reactive can be either solid or pearlized but do NOT contain any particle additives*.
Particle - Since the mid '90s, granular materials have been added to increase the traction of existing reactive coverstocks. Known commonly as 'Particle' these coverstocks will usually make a ball hook earlier, depending on the type of particle used as well as the particle load.
Urethane - Urethane coverstocks are a non-porous material that provide less friction than reactive resins. Urethane does not have the backend hook potential of reactive or particle coverstocks and will not absorb oil.
Polyester - Polyester, or 'Plastic' as they are commonly called, is a non-porous material that creates the least amount of friction of any coverstock discussed in the BBI websites.
*Some manufacturers use glitter or other sparkling materials to achieve a particular appearance. These materials are added for asthetic purpose and are not designed to alter the coverstock's performance. | 
