Both my 17 and 17L gen 1 have these parts. This is interesting info. Thanks!Rewind, Glock STILL has never publicly addressed the "upgrade" (Recall) they did in the 90's with their changeover from the black coated internal parts to the silver.
To make a long story short, the NYPD adopted them, they burst fired or ND's when the gun was loaded, Glock said it wasn't possible, NYPD hinted they were trading them all for Ruger's, Glock sent out 18 wheelers with machine shops in them to modify the internal parts while new ones were being produced, they produced the "upgrade parts" fixed it all and changed over to the new parts. To this day they have never told the public, and if you find a Gen 1,2 gun with black internal parts they will swap them all no questions asked.
Obviously their guns are reliable and safe now, but even Glock went thru this, but they kept it out of the public. Theirs is a case study on how a major manufacturer can move past a problematic product.