(Compatible with DJI Inspire 1 / Pro / v2 and Matrice 100. 4x 21mm 7075 propeller adapters. adapters are only for NON-folding propellers). The mounts are machined from 7075 aeronautical Aluminum alloy (Ergal), by world-leading 5 axes Hermle CNC milling machines, within 20 microns of tolerance.