This is a Rectify Series drop-in speaker system for nonsound-ready Atlas Trainman RS-32/36 locomotives. The speaker is a beautiful press-fit between the rear weight and motor mount. No frame/weight/shell modifications are needed! Decoder installation can by simplified with a Nix Trainz Decoder Buddy and a 21-pin decoder, or you can hard-wire a decoder in. PCB-style decoders (PNP, Direct) will not fit due to their length.
 
The speaker comes fully assembled and tested.