It also fits the AM-26/AIC-2 interphone amplifier that began replacing the RC-36 (BC-347) interphone amp in 1944. It sorta looks like a bare aluminum command receiver. On 3/17/2015 7:01 PM, mac via ARC5 wrote: > Cleaning up and out. Came across an MT-28/ARN-5. Good condx. > > Anybody interested? > > Dennis D. W7QHO > Glendale, CA