Billenium is berettas spray finish that mimics stainless. Its what berreta uses to sorta match the gun finish. Its used on parts that arent stainless steel to mimic the color pattern. Some people can discern the difference in color others cant. Just depends on how well you see different shades.
Stainless steel isnt a finish its the bare base metal buffed/blasted to various looks. Unless a part is made from the same metal as the rest of the gun finished the same way there is going to be very subtle differences in color regardless
I would suggest buying one cheap small part see how well it matches then get the rest.
"Gun control: The theory that a woman found dead in an alley, raped and strangled with her panty hose, is somehow morally superior to a woman explaining to police how her attacker got that fatal bullet wound." — L. Neil Smith
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