MH-66A4B Intrinsically Safe Submersible Speaker Mic
MH-66A4B Intrinsically Safe Submersible Speaker Mic
IP57 Rated • Intrinsically Safe • Submersible • Vertex Standard • Integrated PTT
The MH-66A4B Intrinsically Safe Submersible Speaker Mic is an IP57-rated, waterproof remote speaker microphone built for Vertex Standard portable two-way radios. Its intrinsically safe, submersible design makes the MH-66A4B the right choice for crews working in wet, dusty, or hazardous environments who need clear, hands-free audio without pulling the radio off their belt — a rugged upgrade for any compatible commercial two-way radio.
Who It's For
Choose the MH-66A4B if your team runs Vertex Standard VX or EVX radios in demanding conditions and needs a sealed, intrinsically safe speaker mic. Prefer a lighter everyday option? Compare the MH-360S Compact Speaker Microphone or the MH-450S Medium Duty Speaker Microphone.
Key Features
IP57 Submersible
An IP57 rating means the MH-66A4B is dust-protected and built to survive temporary immersion in water — ideal for rain, washdowns, and wet job sites.
Intrinsically Safe
The intrinsically safe construction makes the MH-66A4B suitable for hazardous and demanding environments where standard accessories fall short.
Hands-Free Audio
Clip the speaker mic to your shoulder or vest and talk or listen without removing the radio from your belt or case — clear audio right where you need it.
Vertex Standard Fit
Purpose-built for Vertex Standard portable two-way radios across the VX and EVX families, so it drops straight onto your existing fleet.
Compatible Radios
The MH-66A4B Intrinsically Safe Submersible Speaker Mic is compatible with the following Vertex Standard portable two-way radios: VX-231, VX-260 Series, VX-350 Series, VX-450 Series, ISVX-450 Series, EVX-261, EVX-530 Series, and ISEVX-534.
Running a different platform, or not sure the MH-66A4B fits your radios? Browse our full business two-way radios and commercial two-way radios collections, or reach our Canadian radio experts to confirm compatibility — call 800-681-8023 or contact us.
Want to weigh your options? The MH-450S Medium Duty Speaker Microphone covers a broad range of VX and EVX models, while the TW-300V Industrial Speaker Mic adds a listen-only headset jack for heavy-duty industrial use.
Shop Commercial Two-Way Radios →
Frequently Asked Questions About the MH-66A4B Speaker Mic
• Is the MH-66A4B speaker mic waterproof?
Yes. The MH-66A4B carries an IP57 rating, meaning it is dust-protected and submersible — built to withstand temporary immersion in water. That makes it well suited to rain, washdowns, and wet work environments.
• Which radios is the MH-66A4B compatible with?
The MH-66A4B is compatible with Vertex Standard VX-231, VX-260 Series, VX-350 Series, VX-450 Series, ISVX-450 Series, EVX-261, EVX-530 Series, and ISEVX-534 portable two-way radios. If you are unsure whether it fits your radio, call 800-681-8023 or contact our Canadian team to confirm.
• What does intrinsically safe mean for this speaker mic?
An intrinsically safe accessory is engineered for use in demanding and hazardous environments. The MH-66A4B's intrinsically safe, submersible construction lets crews communicate clearly in conditions where a standard speaker mic would not hold up.
• How is the MH-66A4B different from the MH-360S and MH-450S speaker mics?
The MH-66A4B is the rugged, IP57-rated, intrinsically safe and submersible option for harsh conditions. The MH-360S Compact Speaker Microphone is a lightweight everyday choice, while the MH-450S Medium Duty Speaker Microphone sits between them and fits an especially broad list of VX and EVX radios.
