Rockford Fosgate RM18D4 Prime 8″ Dual 4-Ohm Subwoofer
NOW DISCONTINUED
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The RM18D4 is a white 8” Prime R1 subwoofer designed for marine watercraft or powersports applications. It features color matched grille and is UV and moisture resistant. Can be used in sealed, vented or infinite baffle installations.
- True Marine Grade compliance
- 100% UV stable ASA injection molded plastic parts
- Injection molded mineral filled polypropylene cone body with UV inhibitors
- UV and salt fog resistant Santoprene surround
- Ultra-flexible fully insulated silicone lead wire
- Proprietary corrosion resistant spring loaded push terminals
- Moisture, tear and fatigue resistant Aramid fiber spider
- Removable trim ring/grille
- Available in black or white
- 2 Year Warranty

Element Ready™ – Subwoofers
These subwoofers are protected against Dust, UV, Water, Corrosion, and feature Stainless hardware.

CEA-2031
Power handling on Rockford Fosgate speakers conform to CEA-2031 industry standards.

Klippel Verified
Klippel is a speaker certification program allowing us to deliver the best possible subwoofers.

ASTM Test Standards
Marine Grade standards ensure resistance to extreme environments.

VAST Surround – Marine
The Vertical Attach Surround Technique significantly increases a subwoofer’s effective radiating cone area up to 25%.

FlexFit 2 Basket – Marine Sub
The slot mounted frame pattern allows for variable adjustments to the mounting position of the subwoofer.

Anodized Aluminum Voice Coil Former
Rockford Fosgate subwoofers use anodized aluminum voice coil formers for superior heat dissipation (up to 100° …
RM18D4
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