BOYESEN REED REPLACEMENT RAD-40B PSR-040The latest carbon fiber technology with all the advantages of Boyesen's dual stage reed design, Responds quickly and accurately to changes in piston speed for smooth, dependable throttle response, Offers the quickest acceleration any reed can offer; maximize horsepower and torque, Utilizes a carbon fiber top reed and a durable fiberglass epoxy bottom reed, No sacrifice in reed life like traditional carbon fiber reeds