We have tested the VTX03 with runcam micro swift」ャ which is very suitable and compatible.
https://www.wish.com/c/599540dda111de4b4cf13bb4

Package Included:
1 X FPV Transmitter
1 X IPEX antenna

Specification:
Brand name: Eachine
Item name: VTX03 Super Mini FPV Transmitter
Output power: 0/25mW/50mW/200mW switchable (Set output power on 0」ャ to avoid frequency interference)
Input voltage: 3.2-5.5V
5V camera supply」ャ 570mA(MAX)---200mW
5V camera supply」ャ 450mA(MAX)---50mW
5V camera supply」ャ 360mA(MAX)---25mW
Video system: NTSC/PAL
Antenna dimensions: 55mm X 5mm diameter
Antenna: IPEX
Frequency: 5.8GHz 9 bands 72 channels」ャ with Raceband: 5325-5945 MHZ
Size: 21.43*15.20mm(L*W)
Weight: 2.97g

Operation:
-Powering on the VTX」ャ blue LED display 0」ャ indicating the VTX is powered on 」ャ but it is in off status without any transmission.
-Short-press the button to change channel(CH)」ャ digital display will change synchronously. Digital display changes cyclically from 1 to 8.
-Long-press the button for 2 seconds until digital display flicker. Then short-press the button to change the frequency band(FR)」ャ digital display will change synchronously. Digital display changes cyclically from A」ャ B」ャ E」ャ F」ャ R」ャ U」ャ O」ャ L」ャ H.
-Long-press the button for 5 second until digital display flicker. Then short-press the button to change the power」ャ 25mW/50mW/200mW(one hyphen stands for 25mW」ャ two hyphens stand for 50mW」ャ and three hyphens stand for 200mW).
-5 seconds after setting」ャ CH」ャ FR and power will flicker alternately.

NOTE: The VTX has memory for setting. To change the setting」ャ please repeat steps as above.