This is a Rectify Series drop-in speaker system for Rapido RTL Turboliner locomotives (power car). The speaker installs face-down and uses a strap of tape like the stock speaker. No modifications are needed to replace the factory speaker.
 
The speaker comes fully assembled and tested.
 
Dimensions are 11mmH x 24mmW x 32mmL
 
VIDEO: https://youtu.be/BYg2GXcGYWo