Rockford Fosgate M210S4

10" 4-ohm marine subwoofer

Item #: 575M210S4

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Original Price: $249.99

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Rockford Fosgate M210S4

This sub's rugged construction is made for marine use.

Boost the bass on your boat

Rockford Fosgate's M210S4 marine subwoofer gives you outstanding bass performance in the toughest conditions. Handling up to 250 watts RMS, it keeps the party going whether you're on the water or in the marina.

Designed specifically for marine and powersports applications, this sub stands up to the extremes of wind, water, salt, and sun. The injection-molded polypropylene cone is made with UV inhibitors, while the TPE (Thermo-Plastic Elastomer) surround resists punishing sunlight and moisture. The removable 16-gauge stainless steel grille cover looks great and withstands corrosion.

Inside the sub, magnetic shielding helps you stay on course by minimizing the electromagnetic interference that can affect your guidance systems. Proprietary corrosion-resistant, gold-plated terminals and a fully insulated, ultra-flexible lead wire help ensure reliable performance. This sub is suitable for use in sealed, vented or infinite baffle installations.

Product Highlights:

  • 10" 4-ohm marine subwoofer
  • internal magnetic shielding reduces electromagnetic interference
  • injection-molded, mineral-filled, polypropylene cone with TPE surround
  • UV-stable Centrex® injection-molded plastic parts
  • durable Aramid fiber spider
  • corrosion-resistant, gold-plated terminals
  • power handling: 250 watts RMS (500 watts peak)
  • top mount depth: 5.54"
  • warranty: 1 year
  • Our 60-day money-back guarantee
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Hands-on research

What's in the box?

Download owner's manual

  • 10" Marine subwoofer
  • White polymer and stainless steel grille
  • Four 2" Stainless-steel Allen head screws
  • Four 1-1/4" Stainless-steel Allen head screws
  • 4mm Allen head bit
  • Owner's manual (English/ French/ Spanish/ German)

Product Research


Marine Tested: Rockford Fosgate's M210S4 marine subwoofer is subjected to ASTM B117 and ASTM D4329 test standards to ensure it can withstand the corrosive effects of salt/fog, as well as sunlight, moisture, and heat.

Woofer: The subwoofer features an injection-molded, mineral filled parabolic polypropylene cone with UV inhibitors. The TPE (Thermo-Plastic Elastomer) surround is also UV and salt/fog resistant.

Centrex Basket: The basket and other plastic parts are made of UV stable Centrex injection molded plastic.

Magnetic Shielding: The motor structure is magnetically shielded to reduce the potential for electromagnetic interference.

Compression Terminals: The M210S4 features spring terminals which accommodate pin connectors, single banana plugs, dual banana plugs (standard 3/4" width) or bare speaker wire up to 10 gauge.

VAST Surround: The Vertical Attach Surround Technique (VAST) increases a speaker's effective radiating cone area without increasing the size of the basket.

FlexFit Basket: The Flex Fit frame utilizes slots (where possible) instead of single screw sized holes; allowing slight adjustment of the speaker when mounted.

Mounting Hardware: Marine-grade stainless-steel mounting screws are included.

Enclosure: The M210S4 can be mounted in a sealed or ported box, or in an infinite-baffle (free-air) application. The optimum internal volume of a sealed enclosure is 0.75 cubic feet (from 0.5 to 0.85 cubic feet is acceptable). The 0.75 cubic foot enclosure yields a -3dB point of 60.6 Hz. The best ported enclosure volume is 1.25 cubic feet using one 4" diameter x 8.52" long port; this yields a tuning frequency of 48.6 Hz and a -3dB point of 40 Hz.

Our Product Research Team

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