What size screwdriver to resize ZF Tudor Black Bay v4?

[wanged]

I've read 1.4mm for the gen, but someone else on this forum said 1.4mm was too big for his ZF V2

I am sure there are many V4 owners on these forums. What size screwdriver did you use?

Thanks

 

[rgercya]

because with resizing them as I broke 2 screws trying to resize.. i was using a 1mm or 1.2 i believe.