Ft-241 case, will be marked channel 333,and 33.3 MCS. Buy or trade. They were used in the old BC-683 tank transmitters, I believe. Thanx Lloyd Please visit my web site http://www.lloydsdipsydumpster.com/ Lloyd Godsey KK7IZ 1315 N. Udall Circle Mesa, Az 85203 480-620-7145 (cell)