This WORKER MOD Flywheels have redesigned to promote the motorized blaster shooting range and dart speed. The lightweight flywheel enhance the motor spin acceleration so each shot could enjoy the maximum power. The flywheels have a flat Diamond pattern surface that best use with the canted cage, the high friction surface give maximun power to turn the darts. Advance modding skill require, you need to disassembly the blaster and remove the motor module. The serrations add extra grip for the dart under high crush applications, but they do add extra dart wear. They offer higher velocities than most other wheels, but sacrifice dart wear, and noise. Sold as a pair. These wheels have a very tight shaft fit! Make sure you brace the back of your motors as you press them on. Standard (Blue) Diamond Pattern Diameter: 34.0mm Muzzle Velocity: High Accuracy: Very High Dart Condition: Bad High Crush (Orange/ Silver) Diamond Pattern Diameter: 35.0mm Muzzle Velocity: Very High Accuracy: Very High Dart Condition: Very Bad