The 12" "Stump Thumper" measures 10" in the mold, 12" on the fall. It is a big worm with a thick tail that is really a hybrid between a "C" tail and a "U" tail. It really puts off some serious vibrations under water. You can experiment with your plastic hardness and get more of a finesse presentation, or a serious thump out of this worm.
This mold is available as an injection or open pour mold. See the open pour section for the OP version.
Additional pictures can be seen here:
Photo Gallery Single Cavity.