The MOBULA propeller is made with carbon fiber to ensure its light weight and Strong 
Each Propeller is marked With CW or CCW (clockwise or counter-clockwise) it is impotant when replace=ing blades that you match the marking CCW with the CCW marking on the propeller and CW motors With CW propellers.
 
This Is a complete set containing 2x CCW and 2x CW propellers.