This is a Rectify Series drop-in speaker system for the first-run Athearn RTR SD40/45T-2 Tunnel Motor locomotives. More than just a box, the enclosure features Diapasonic Tuning™, which allows the lower frequencies to accurately develop and resonate, clears the midrange of excess resonance and tunes the upper-mid/high response. The driver fires downward over the radiator opening and the entire system remains clear of the screens. A hole is provided on the mounting tab to route the truck and speaker wires through. The speaker mounts in place of the rear weight and uses either the weight screws trimmed short or any short 2-56 screws. No frame or shell modifications are needed to install the speaker!
 
If you remove the small, screwed-on weight behind the cab you can stick a front-mount speaker there using the AHGS-2845.
 
The speaker comes fully assembled and tested.
 
Dimensions are: 16mmH x 17mmW x 68mmL