These are Rectify Series drop-in speakers for Intermountain F-Unit locomotives. Two A-Unit versions are available; early-run non-sound and current-run sound-ready.
Additionally, a B-Unit system is available that fits the space where the cab would be. It features a wire-loop to keep the speaker wires off the drive-shaft. You can use this speaker singly or combined with one of the rear-mount speakers (depending on your frame version) for maximum impact.
More than just a box, the enclosures 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 speakers use carpet-tape or a touch of adhesive to mount and no modifications are needed to replace the factory speaker.
The speakers comes fully assembled and tested.
Early: 12mmH x 26mmW x 32mmL
Current: 13mmH x 28mmW x 40mmL
B-BOMB: 16mmH x 30mmW x 41mmL