ok, most likely M1
Seems like this is what Juin is advertising..
M1 - MTBs
F1 - Road, Gravel bikes
R1 - Cyclocross
Just to note, Juin is not a full hydraulic, I'd personally recommend you getting full hydraulic brakes.
CitizenCyle (YouTube channel) said that Juin Tech isn't much better than stock cable brake.
Maybe a little bit, but you won't feel a big difference.