brake callipers

[iain]

Hi Guys...
Does any one know about the stamped numbers on the inside of the brake callipers...I have three sets..

They all have one and a half stamped on them..   
One set has B1
                  B2

Set two has D2
                  D3

Set three has B4
                    D4

Iain
NZ

[h2olawyer]

Ooh!  That's a great question!  Something new to research!  Wish I knew the answer.  Anything I'd say at this point would be pure speculation, so I'll keep my fingers from typing my initial thoughts.   ;)

H₂O