The three speaker-mic connector families

Almost every HT speaker-microphone uses one of three connector systems. Buying the wrong one means it physically will not plug in.

Kenwood 2-pin (the de facto standard)

Two jacks on the radio: a 2.5mm jack for the speaker and a 3.5mm jack for the microphone. This is the most common speaker-mic connector in amateur radio because virtually every Chinese HT manufacturer copied the Kenwood pinout.

Radios that use Kenwood 2-pin: All Kenwood amateur HTs (TH-D74A, TH-D72A, TH-K20A, etc.). All Baofeng radios (UV-5R, UV-82, BF-888S). All Wouxun radios. All BTECH radios. All TYT radios (MD-380, MD-UV390). All AnyTone radios (D878UV, D868UV). All Retevis radios. All TIDRADIO radios. All Radioddity radios (GD-77, GA-510). Most Alinco HTs.

Compatible speaker-mics: Any speaker-mic labeled "Kenwood compatible" or "Baofeng compatible" will work with all radios in this group. The cheapest option is $8 on Amazon; the quality option is the Kenwood KMC-45D (~$25).

Icom 2-pin screw-on (proprietary)

Two screw-on jacks on the radio with a proprietary thread pitch. Physically similar to Kenwood 2-pin but NOT interchangeable — the screw threads are different and the pinout is different.

Radios that use Icom 2-pin: All Icom amateur HTs (ID-52A, ID-51A, IC-T70A, IC-V86). Icom marine HTs. Icom commercial portables.

Compatible speaker-mics: Must be labeled "Icom compatible." The Icom HM-186LS (~$35) is the OEM option. Third-party Icom-compatible speaker-mics are available.

WARNING: Kenwood-compatible speaker-mics will NOT work with Icom radios. The connectors look similar but the thread pitch and pinout are different. Forcing a Kenwood speaker-mic into an Icom radio can damage the connectors.

Yaesu (varies by model)

Yaesu has used multiple speaker-mic connector systems across different HT generations. There is no single "Yaesu standard."

Current Yaesu HTs (FT3DR, FT5DR, FT-65R, FT-25R): Use a combined 3.5mm/2.5mm connector arrangement. Check specific model compatibility.

Older Yaesu HTs (VX-6R, VX-7R, VX-8DR, FT-60R): Different connector arrangement from current models.

Compatible speaker-mics: Must be labeled for your specific Yaesu model or model family. The safest approach is buying the Yaesu OEM speaker-mic for your specific radio.

Motorola commercial (proprietary)

Motorola commercial radios (CP200d, XPR series) use a multi-pin proprietary connector that is completely incompatible with amateur radio accessories.

Quick lookup

Baofeng UV-5R: Kenwood 2-pin
Quansheng UV-K5/K6: Kenwood 2-pin
AnyTone D878UV: Kenwood 2-pin
TYT MD-380/MD-UV390: Kenwood 2-pin
Yaesu FT-65R: Yaesu-specific (check model)
Yaesu FT3DR/FT5DR: Yaesu-specific (check model)
Icom ID-52A: Icom 2-pin screw-on
Icom IC-V86: Icom 2-pin screw-on
Kenwood TH-D74A: Kenwood 2-pin