BM and VM designations for Nuts and Bolts in PET

[O875]

I was checking what bolts are supposed to be on the car and came across things marked BM and VM. The M looks to be metric but what do the V and B mean please?

[Tom]

ChatGPT says this:
BM
B = Bund (flange)
M = Mutter (nut)
BM = standard hex nut (with or without flange, depending on part)
No prevailing torque feature implied by the code itself.
VM
V = Verformt (deformed)
M = Mutter (nut)

Seems plausible....