This is the 4-TH (Square) to Old (Round Port) Trainer Cord from Tower Hobbies. FEATURES: Allows the connection of a transmitter with a new square mini trainer plug to a transmitter having the old round port plug INCLUDES: One Tower Hobbies mini to round trainer cord REQUIRES: Connecting between the two trainer ports of each transmitter SPECS: Length: 10.2" (311cm) COMMENTS: For the 4-TH to 4-TH (square to square) trainer cord, order TOWM6081 This trainer cord can be used with HiTech radios as "students". Unfortunately you can not use a HiTech radio as a "teacher/master" radio. It is recommended that the "student" radios should be shut off. jxs 11/17/04 ir/jxs updated jpg 1/9/06