BOSS Audio MGR350B

Last updated: November 7, 2026

BOSS Audio MGR350B
2.7/5#6 of 10 in gauge-hole marine stereos
2.7

A step up from the MGR300B for a gauge-hole install, with better water resistance, a weather band and a subwoofer output.

  • 1Zones
  • IPX6Water rating
Check price at Amazon$178.94

Price checked November 7, 2026. As an Amazon Associate we earn from qualifying purchases.

Pros
  • Fits a 3 in gauge hole
  • IPX6 front with UV coating
  • Weather band plus front, rear and subwoofer pre-outs
Cons
  • No power rating published
  • No warranty published by the maker

How it scores

The rating comes from 7 measured or published factors, each scored 0-100 against fixed reference points for its mount. How we rank explains each one.

Specifications

Model numberMGR350B
Audio
Zones1
RCA output sets3
Sources and control
BluetoothYes
USB playbackYes
Phone appNo
SiriusXM-readyNo
NMEA 2000No
Wi-Fi or AirPlay 2No
Weather bandYes
DAB+No
CD playerNo
Camera inputNo
Build
MountGauge hole
Front water ratingIPX6

Alternatives in this mount

Kenwood KMR-M300BT

A full-featured gauge-hole stereo for a small boat or powersports dash. Spend more on the eXcelon KMR-XM500 only if you want its 5 V pre-outs and longer warranty.

Amazon $299
$299
19 W x 4 RMS1Gauge hole

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