I think those battery shells that hold double A. batteries nowadays are mainly for monitoring purposes. I have one for my adi A.T.-600 and I can't get much transmitting power out of it where as with my old Icon 24-A.T. I got pretty good transmitting time out of it. It might be a better investment these days to just get an extra battery pack of the longest life available for whatever rig you have. 73. Harvey Heagy (N.5.H.A.U.) "evil people prosper because good people do nothing."