# Poly-Planar MB-21 8 Watt VHF Extension Speaker - Black [MB21B]

**MB-21 8 Watt VHF Extension Speaker - Black**

This compact marine communications speaker includes a stainless steel mounting bracket and stainless steel grill. 

These waterproof communication speakers can be mounted where you can hear your VHF radio.

**Features:**

-   Completely waterproof and corrosion-proof
-   Features stainless steel grills, sturdy plastic frames, polypropylene speaker cones and Teflon-coated wires
-   10' Lead wire w/mini-plug and RCA adapter 

**Specifications:**

-   Peak Power Handling - 8 watts
-   Continuous Power - 4 watts
-   Speaker Impedance - 4 ohm
-   Weight - 0.35 lbs per speaker
-   Overall Dimensions - 2-15/16" x 2-3/4" x 1-5/16" (74mm x 69mm x 33mm)

\*Sold as a Single

**This product may not be returned to the original point of purchase. Please contact the manufacturer directly with any issues or concerns.**

**Specifications:**

-   Type: Speakers
-   Box Dimensions: 2"H x 5"W x 8"L WT: 0.5 lbs
-   UPC: 731128002118

  
[Quick Guide (pdf)](https://productimageserver.com/literature/quickGuide/11236QG.pdf)

## Details

- **Price:** 21.99 USD
- **Type:** Accessories
- **Tags:** 1st Class Eligible, Brand_Poly-Planar, Clearance, Communication, Communication | Accessories, Specials

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 21.99 USD | In stock |

## Images

- Poly-Planar MB-21 8 Watt VHF Extension Speaker - Black [MB21B] Poly-Planar

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> Source: [Besafe1st](besafe1st.com/products/poly-planar-vhf-extension-speaker-8w-surface-mount-single-black-mb21b)
> Updated: 2026-06-10