These are our OEM 5mm - 3.17mm CarbonBird™ Prop adapters featuring 3 blades/petals/leaves to grip the shaft evenly - like a three legged stool these adapters grip evenly - With Multicopters it's critical to have a 100% perfect straight/true collet shaft to ensure the prop is rotating dead-centre. In the event of impact the CarbonBird™ motor shaft will usually fail at the machined failpoint (small groove machined into the shaft) but if the shaft is reversed then these force can be absorbed by the Collet (this item) and it may be off centre - and is best replaced.
Dimension & Data
Shipping - Does not fit into the maximum width dimensions of a $3 envelope - must be included with a "package" sized order - ordered with other things - any order attempting to add 1 or 2 of these prop adapters by airmail envelope $3 - will be cancelled and refunded because it does NOT fit inside an envelpe for airmail with the appropriate packaging - simple - sorry
*NOTE : Its possible to bend an aluminium collet straight by first spinning it - marking the side which is running wide with a permanent ink marker - then bending it away from the mark by the same amount - be aware that metal fatigues oif bent back too many times and may fail.
NOTE : 2 - if the washer is slightly off centre - don't panic - use this to your advanatage to balance a prop which has a lateral imbalance - ie - sit flat across the balancer.