as far i know most of/all the Master Piece are in house movement
the watch that i have was the latest ML automatic movement with 57 jewels.... 
what do u mean by in house? to me


this is the so call full in house movement.... the handwind chrono

all the auto chrono still using eta7750 base... not even modification i guess.... but not sure what grade!


this is the so far most complicated in house in ML, chrono with memory


all these retrograde handwind ML watches is using eta unitas 6497/8 with add on retrograde module....
since 2 yrs ago it ML redesign the 3/4 plate instead of

just polishing old unitas bridges, bigger jewel, perlage base plate, added regulator....


these skeletons is still stand eta 6497-1 with skeleton done by others maybe?


this handwind ML last time used Peseux 7046, but after no longer in production, ML using eta 2801 instead....
but its much better finishing than the standard eta 2801, blued screws, gold chaton....


these r also eta with standard module.... many other watch brand using same movement...

this is latest creative module from ML....