Evidently the razor handle I have is not an Atra Plus as I believed, but some later model that takes a different blade. So now I need to buy an Atra Plus compatible razor handle to use the blades I just bought. Not happy, but it's my fault.
Last purchase of the same had 1 bad blade in it or otherwise a 5.
The price for these blades are not expensive and They are great blades and the price is affordable.
The price is great and the Gillette Atra is outstanding.