This is a set of molds, cores and jigs to make your own molded carbon fiber rudder for an IOM or other one-meter R/C sailboat.

All of the instructions for use are in my build thread on RCgroups.com It is an involved build, not something you are going to do in an hour. The instructions are detailed and long, be prepared!

https://www.rcgroups.com/forums/showthread.php?4164819-How-to-make-sailboat-rudders-and-keels-in-6999-easy-steps

The result is pretty decent rudder that you can go racing with and further customize to get the weight and strength you need.