There are three known types of Feather DE razor blades.
Hi-Stainless These are the older blades that came in the black and gray package. They are not platinum coated and are no longer produced.
NeW Platinum Hi-Stainless These are platinum coated blades that were produced along with the non-platinum blades back in the 80's. They have "Platinum Coated Blade" and "NeW HI-STAINLESS" printed on the blade. They do not have the Feather logo or "TRADE MARK" printed on them. They were discontinued along with the non-platinum blades in 1988.
Platinum Hi-Stainless These are the current production platinum coated blades in the new yellow & red package BUT with the old style printing on the blade. They also have a new triple bevel edge.