Boss MC420B

All-terrain Bluetooth® speaker and amplifier system (Chrome)

Item #: 104MC420B

In Stock

6 Reviews

Your price: $89.99 Earn up to 90 Rewards points

Add to Cart

+ Add to wishlist + Email me alerts for this product

View all associated offers

Take it outside

Do you have a motorcycle or an ATV without a way to hear your favorite tunes, or a boat that needs accompaniment? Do you want to stream music from your phone or other Bluetooth-equipped device? This MC420B speaker system from Boss can satisfy your needs. It's weatherproof: the MC420B's components, including the speakers, circuit boards, and amplifier connections, have been specially coated and sealed to protect against damage from water and weather. And it's Bluetooth enabled, so you can connect wirelessly to your favorite device for hours of listening pleasure.

Get connected

The MC420B includes an in-line volume control for the two 3” speakers, which include adjustable brackets to mount the streamlined pods to a handlebar or rail. You can plug your media player into the system's minijack input or connect via Bluetooth2.1 — either way,  the system's 600 watts of power will rock the outdoors. And the system's Bluetooth reception range extends up to 33 feet, so you can keep the music playing even when you're not right next to the system. Wherever you go, the MC420B can handle the conditions and pump out the tunes.

Product Highlights:

  • system includes 2-channel amplifier and two 3" speakers
  • marine-grade construction for weather resistance
  • Bluetooth enabled with auto pairing and reconnect
  • peak power output: 600 watts
  • frequency response: 80-15,000 Hz
  • chromed plastic speaker pods
  • multi-function wired remote control
  • includes adjustable mounting brackets
  • dimensions: 3-1/4"L x 3-1/8"W x 1-5/8"D
  • warranty: 3 years
  • Our 60-day money-back guarantee

Boss MC420B Reviews

Average Customer Review:

6 reviews
Review this product
Great Gear Giveaway

Submit a review and then enter to win a $350 rewards card


Review this product:

Thanks for taking the time to share your experiences about this product. Please be sure to focus your comments on the product itself. Read our Review Guidelines for more information.

Your email won't be visible. Please use the email address that is associated with your order.
(e.g., JohnD) Your review will be signed using the display name and location
(e.g., Charlottesville, VA)

Click on a star to rate the overall product on a scale of 1-5
1500 characters left
  Attach a YouTube Review
Crutchfield Video Review Guidelines
  • Only submit videos that you made or are authorized to use.
  • Do not submit videos that contain music, video or visuals that are copyrighted and belong to someone else.
  • Please see our Review Guidelines for more information.
500 characters left
500 characters left

sounds good

Written By gbowers, Missouri on Saturday, August 22, 2015

Crutchfield Customer Review (What's this?)

Sounds good for the $. Easy install on my suzuki intruder. Not great over 60mph but great for around town.

Boss 420b

Written By Don, Illinois on Monday, July 20, 2015

Crutchfield Customer Review (What's this?)

Plays well on my Kawasaki love the Bluetooth very loud and clear

Pros: Easy to Bluetooth phone very good unit for the money

Cons: Did not come with all the spacers to attach speakers to handle bars had to fabricate emailed crutchfield team instead of offering to send them they said hope your work out any further help needed let us know

Quality Product

Written By Brandon, Colorado on Saturday, July 04, 2015

Crutchfield Customer Review (What's this?)

The system was easy to install. The parts are high quality. The sound is awesome.

Pros: Good quality, easy installation.

Love them sound

Written By There the boss, Oregon city, Oregon on Sunday, March 29, 2015

Crutchfield Customer Review (What's this?)




Written By Berly, Florien la on Thursday, November 06, 2014

Crutchfield Customer Review (What's this?)

Very loud and reliable, Bluetooth connection is spot on no issues, Bluetooth range is amazing, pricing is the best Around you will not beat it for the quality

Very satisfied !!

Pros: Bluetooth connectivity on point Speakers are loud and clear No wires dangling everywhere Bluetooth range is good

Cons: Wires or a little too short going to the battery


Written By ELI, Cape Coral on Tuesday, May 27, 2014

Crutchfield Customer Review (What's this?)

Sounded great until the amp stopped working after several days of use. Maybe it was a defective one. Other than that I would of been ok with the kit.

Pros: loud, Bluetooth, volume control knob

Cons: didn't last

Hands-on research

What's in the box?

Download owner's manual

  • 2 Speakers (each with 37" wire and mounting bracket attached)
  • 2-channel amp (with wiring attached)
  • Wired volume control (attached to amp with 76" cable)
  • Two 0.25" spacers
  • Two 0.195" spacers
  • Two 0.155" spacers
  • Two 0.122" spacers
  • Two 0.078" spacers
  • Two 0.040" spacers
  • Two M10x45mm bolts (installed)
  • Two M10 Split lock washers (installed)
  • Two M10 Flat washers (installed)
  • Two M10x30mm bolts
  • Two 5-amp ATO fuses (one installed/one spare)
  • Four 3/4" Self-tapping screws
  • 4 Small split lock washers
  • 4 Small flat washers
  • User manual
  • Warranty information
  • Boss Facebook note

Product Research


Amplifier Inputs: The amp has four inputs; RCA jacks on the amp, a female 3.5mm mini-jack on the amp, a male 3.5mm mini-plug attached to the amp with a 6' cord, and wireless Bluetooth. All four are inputs are live simultaneously, so if more than one is connected, selection must be made by turning all but one source off.

Note: If more than one source connected to the line inputs (RCA and 3.5mm) is turned on, it's likely you'll hear static through the speakers in addition to music, even if the source is muted or paused.

Speaker Mounting: The speakers are designed to mount to a round tube using the adjustable stainless steel clamps. Six different spacer sizes are included for use with tubes from 5/8" to 1-1/2" (approximately). Once the speakers are in place, but before the brackets are tightened, you can adjust the mounting angle. After mounting, the speakers can still swivel almost 360°.

Wiring: All the wiring is fixed length and already attached to the speakers and amplifier. Each speaker has a 37" input wire attached and the wires from both speakers are attached to a single Molex plug. The power and ground wires extend 74" from that same Molex plug and power wire has a 5 amp in-line fuse. The 22" speaker output wires are attached to the amplifier and terminated with the mate to the speakers' Molex plug.

Volume: The rotary volume control has a 76" cable attached that plugs into the amp and mounts in a round hole in a panel, 0.27" diameter.


  • Speakers:
    • Width: 4-1/8"
    • Height: 4-1/4"
    • Mounting Height: 5-1/2" (above center of the bar to which the speaker is mounted)
    • Depth: 4-3/4"
  • Amplifier:
    • Width: 2-5/8" (3-1/8" including mounting flange)
    • Height: 1-5/8"
    • Length: 3-5/8" (4-5/8" including wiring)


  • Voltage: 10-16 volts DC
  • Max Power: 600 watts
  • THD: <0.1%
  • Signal to Noise Ratio: >85 dB
  • Channel Separation: >50 dB
  • Frequency Response: 80 Hz - 15 kHz
  • Sensitivity: 150 mV - 1 V

Extended Warranty: Units purchased from Crutchfield after 3/1/2015 carry an extended warranty relative to purchases from Boss' standard dealer network. The new warranty is 3 years parts and labor.

Our Product Research Team

At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.

Searches related to the Boss MC420B All-terrain Bluetooth® speaker and amplifier system