This is a Rectify Series drop-in speaker system for many Intermountain locomotives using their common 16x35 speaker. It fits the GP10, GP16, U18B and some other IMR units. The speaker features notches for the wires to nestle in. The speaker uses carpet-tape or a touch of adhesive to mount and no modifications are needed to replace the factory speaker.
 
A shorter version is now available. This version is only 3mm shorter but leaves room to install an ESU PowerPack Mini or TCS KA2.
 
The speaker comes fully assembled and tested.
 
Dimensions are: 11mmH x 18mmW x 35mmL