• Dual-Role Operation: Use as a standalone speaker mic for daily patrol. Plug a headset into the Nexus port and the MSM becomes a PTT — speaker auto-mutes, audio routes to your ears. One device, two modes.
• Dual PTT: Oversized front button for quick keying plus a secondary side button — both work with gloved hands.
• Emergency Button: Dedicated bright-orange emergency activation button. Sends the radio's programmed emergency alert when pressed.
• Volume Control: Up/down scroll buttons on the speaker mic body — adjust audio without reaching for the radio.
• Programmable Button: One additional programmable button configurable through radio CPS for channel change, monitor, scan, or other radio-specific functions.
• Amplified Nexus Port: NATO-wired Nexus connector with built-in amplification for low-impedance dynamic headsets — Ops-Core AMP, 3M Peltor ComTac, MSA Sordin, David Clark, and other tactical headsets with U-174/U plug. Speaker auto-mutes when headset is connected.
• IP67 Sealed: Dust-tight and submersible to 1 meter for 30 minutes. Built for rain, mud, and standing water.

The Kenwood multi-pin connector carries full accessory control data, enabling emergency activation, programmable button functions, and volume up/down adjustment directly from the speaker mic — features not available on the 2-pin (K1) connector.

Kenwood NX-5200, NX-5300, NX-5400, NX-3200, NX-3300, NX-3400, NX-200/G, NX-210/G, NX-300/G, VP-5230, VP-5330, VP-5430, VP-6230, VP-6330, VP-6430, TK-2180, TK-3180, TK-5210/G, TK-5220, TK-5230, TK-5310/G, TK-5320, TK-5330, TK-5400, TK-5410, TK-5430, TK-190, TK-280, TK-290, TK-380, TK-385, TK-390, TK-480, TK-481, TK-2140, TK-2148, TK-3140, TK-3148.

The amplified Nexus port is designed for headsets with dynamic (low-impedance) microphones:

• ✓ Ops-Core AMP (via U174 Monaural or Monobinaural Downlead)
• ✓ 3M Peltor ComTac V/VI, SWAT-Tac
• ✓ MSA Sordin Supreme Pro-X (Mil-Spec)
• ✓ David Clark H10-76 series
• ✓ Any NATO-wired headset with U-174/U plug and dynamic microphone

Electret microphone headsets are not supported by this amplified variant. Contact us for electret-compatible custom orders.

The MSM is built for operators who need both modes — speaker mic on patrol, headset PTT on operations. If you run a tactical headset full-time and don’t need a speaker mic at all, the Constant Able is a lighter, simpler, purpose-built PTT.

Constant Able PTTs connect directly to your radio with no speaker mic in the chain. Auto-switching impedance detection handles both dynamic and electret headsets automatically — broader headset compatibility than the MSM’s dynamic-only Nexus port. Available for Motorola APX, Motorola XTS, Kenwood, L3Harris, Hytera, Icom, Baofeng, and NATO 6-pin radios.

The MSM is available for other radio platforms. Select the connector that matches your radio: