i need some sort of coupling for my ss united states doesnt have a good alignment so need good coupling

heres a pic

shafts are 3mm motor output 4mm


thanks nicole

Perhaps the Dumas dog bone set?
http://www.horizonhobby.com/Products...ProdID=DUM2008

Some people don't like the nylon dog bone, and repace it with something scratch built, but
I haven't ever had one break...

Have a look at these sites. There's a little something for everyone.

http://www.wmberg.com/

http://www.sdp-si.com/

Edit: These just showed up here on RCU as well. Maybe they will help you out.
http://www.rcuniverse.com/market/item.cfm?itemId=338993