KTNN-KG-T100 2 Gang Switch Switch
Model reference: KTNN-KG-T100
KTNN-KG-T100 2 Gang Switch

Available from:

Install method:
USB to Serial

GPIO #Component
GPIO00 Button1
GPIO01 User
GPIO02 User
GPIO03 User
GPIO04 None
GPIO05 Relay2
GPIO09 Button2
GPIO10 None
GPIO12 Relay1
GPIO13 Led1i
GPIO14 None
GPIO15 None
GPIO16 None
Configuration (old version)
{"NAME":"Sonoff T1 2CH","GPIO":[17,255,255,255,0,22,18,0,21,56,0,0,0],"FLAG":0,"BASE":29}

All three gang models are equivalent to the Sonoff T1 xCH models and all three gang types have 3 physical buttons in them, just configured by resistors on the daughter board, plus all 3 gang types have all the relay driver circuity in them, just only fitted with the equivalent gang amount of relays. The older -A3 model has the easy access PSF-B04 ESP board in them, the newer -B3 models what appears to be a custom ESP board in them (label of SM-001 v1 see photo) which is much harder to get access, best method is to remove front switch daughter board..

Pictures for reference…