Wolfwhoop Q4 5.8GHz VTX with MMCX Antenna Connector and 0.01/25/200/400/600mW 37CH Switchable FPV Transmitter with Smart Audio Support OSD Configuring via Betaflight Flight Controller

It's similar to the Q3 but has a smaller profile that uses 20x20mm mounting pattern, which be designed for smaller micro builds.
One cool feature about this VTX is that you can mount it on top of your mini FC/PDB stack thanks to the 20x20mm mounting pattern.
OSD configuration using FC Uart (F3/F4/F7 with OSD)
Built-in BEC: 5V camera @under 300mA
One button frequency and power setup
25/20/400/600mW power switchable

Specification:
Input voltage: 7-24V
Extra features: FC Uart, Parameter-adjusting Mode(0.01mW)
Built-in BEC: 5V camera @under 300mA
Output power:
25mW:100mA @5V
200mW:120mA @5V
400mW:180mA @5V
600mW:220mA @5V
Antenna connector: MMCX
Port connector: JST,6pin
Dimensions: 26(W)X26(D)mm, 20X20mm(hole)
Weight: 4.6g(excluding antenna)
Kit contents: 1XVTX, 1XMMCX pigtail, 1XCable

Note :

5645/5925/5945(E4/E7/E8) are not available sue to FCC regulation. Selecting 5645/5925/5945(E4/E7/E8) will be invalid action.

37 channels are all above 5650 and below 5925MHz, which are legal to use in the USA with an amateur radio license.

This equipment is being sold under FCC's amateur radio rules. Operators must require amateur radio license to operator legally in the US. Use of amateur equipment without a license or use of equipment on restricted frequencies could subject the operator to significant fines by the FCC. By purchasing this equipment, the user is agreeing that they understand these responsibilities and will operate the equipment legally. More information related to ARL, please go to http://www.arrl.org/getting-licensed.