My IRIS came with two Propeller Fastener kits, that include this:
Two interesting things:
- This Propeller Fastener doesn't actually match the one that is on the IRIS. It's longer.
With that you would have to replace all four Propeller Fastener at the same time. But there were only two of them included.
Also I can't seem to find additional such Propeller Fastener kits on 3DR's website.
- The washer that was mounted on the IRIS (top left in the picture) eats itself into the plastic prop, when the screw is tightened. Here it might make more sense to have this washer on the prop and then add the disk (middle right in the picture) on top of that.