oops....ignore my last comment about bossjay. he said the hole was 5mm in this response but he states 4mm in the response for the previous question. he might just be posting generic answers for credits. i could be wrong and it could be a typo. either way his answers seem unreliable. sorry bossjay
I have a spare of this JXF 7x6 prop. I did double check the diameter of the whole and indeed the diameter is 5mm.Tthe thickness of the hub is also 9mm. I made an error in my answer to JRBeaman. I'm Sorry JRBeaman. sfactor1, Thank you for calling this issue to my attention.
The Shaft suits a 4mm but easy to drill out. Shame there are no shaft adapter rings but perhaps many modellers have a good collection. Be ready for a relatively heavy prop. These are not light. I only use these props on aircraft that need a little more nose weight. Sometimes these need a bit of balancing, too. Worth checking.