E-Flite Blade 350 QX / 350 QX2 CNC Machined Prop Adapter Set. CW and CCW Threads. Included: 2 CW and 2 CCW Prop Adapters with hex nuts, washers, and screws. CNC Machined from Billet Aluminum 6mm shaft for carbon fiber or APC style props with 6mm hub or ring kit Very strong and light weight Each adapter package labeled for correct motor installation