These are the DJI™ OEM Spinners (bolts) for dji Phantom motors Gen 2 - this included Phantom 1.1.1 and Phantom 2 and Phantom 2 Vision when combined with after market props such as the HQProp 9443 here or any prop with a 8mm ID.
12mm spanner required (not included) - we recommend a fraction of a drop of Loctite™ 241 blue thread locker on all spinners (NEVER apply too much !)
4 x Spinners - 2*Black left hand thread for CW props ; 2 Silver normal Right hand thread for CCW props - as per photo
NOTE : These are not self tightening, nor were the originals that come on a Phantom! - we dont agree with that phrase- it is a very poor term of phrase - they must in fact be fully tightened by the user in the first instance - however the prop will continue to apply a force in the direction of the tightened position - please study the photos to be sure which are right hand threaded and which are left threaded. Must not be used on a motor spinning BACKWARDS !