Dean, I have heard of that PB shield connection but can not say for sure. I offered the pic because folks were speculating on whether Parker barrels had ID markings. Though this gun is not damascus it does show that barrel markings did exist and that at least in the early years the gunsmith knew what he had for his order not simply because of what bin he pulled the barrels from but what was stamped on the barrels (either by the barrel maker or Parker or both). Regards Ron