need motor coupler help

[mabublitz]

I have these two products and i need help finding a motor coupler that will work for it. its going in a micro hrydro.

http://www.offshoreelectrics.com/proddetail.php?prod=oct-oc098L-24c
and
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=5145

4mm shaft on the motor and .098 flex cable

i got this and it was too small on the motor side.
http://www.offshoreelectrics.com/proddetail.php?prod=oct-ocfhe18098

any opinions? thanks for the help.

[martin]

What micro hydro are you putting it in, Thats a large motor to put in most micro hulls. Martin.

[mabublitz]

its going into a 17 inch skunkworks