Note: Duck Commander has discontinued the inclusion of a bonus CD.TRIPLE REED, POLYCARBONATE DUCK CALL: For years we have tested and tweaked the double-reed system Phil Robertson patented almost 40 years ago.Through trial and error and the input of skilled members of the Duck Commander 'fraternity,' we have developed a patent pending triple reed system.The prototype of this innovative call has been used this duck season and the results have been lethal.The triple reed system is designed to replicate the mallard hen in her quack, feed call, and hail call.This unique system replicates these sounds more easily, due to the different combination of reed material stacked together.The result is a pure duck sound with a little extra kick, and a system that is easy to clean, tune, and operate.