The DJI Matrice 300 Propellers (2110) have been designed for the DJI Matrice 300 RTK. Propellers are sold in pairs consisting of one CW and one CCW propeller. To replace a whole set or purchase a full set of spares, you will need a quantity of two (2) pairs. The 2110 version of Matrice 300 propellers is the “standard” version that comes with the Matrice 300 RTK, also available are 2195 model of propellers which are to be used for high altitude flying. Please reference the DJI Matrice 300 RTK user manual for further guidance on when to use standard vs. high altitude propellers.