Catchers not only have to account for balls in the dirt and use their body to stop them, they are also most probable of getting into a person to person collision. In recent years this percentage has gone down drastically due to rule changes. However, the catcher still has to put their bodies on the line the most during the game.
The Nutty Buddy was invented by Mark Littell, a former MLB pitcher, and is made out of polycarbonate lexan. Polycarbonate is a durable material that is lightweight yet has a high impact resistance, which is one of the reasons it is found in so many products including riot shields. One of the characteristics that makes it special is that it is able to withstand extreme plastic deformations without shattering, which is uncommon in thermoplastics.
The properties of lexan that make it perfect for this application to baseball protective cups include: light average density of 1.21 g/cm^3, Young's Modulus 2.0-2.4 GPa, Tensile Strength of 55-75 MPa, Izod Impact Strength Test value of 600-850 J/m, and its Elongation at Break 80-150%. These and many other properties of lexan make it useful in other applications such as safety features in electronics, construction materials, data storage in the form of DVD's and Blue Ray discs, as well as security components for railroad, automotive, and aeronautical applications.