Gillette bought Astra in 1996, so I emailed Gillette and asked them what the numbers are for. Maybe they will email back!
Could someone please end this mystery for me...thanks.
I am sure at some point in the past this question has been answered...What is the purpose of the numbers 1,2,3,4 on razor blades? Could someone please end this mystery for me...thanks.
So I mentioned that I emailed Gillette to find out about the numbers on the blades and here is their response.
Thanks for contacting Gillette.
We have limited information on Astra blades, as they aren't typically sold in North America. However, per R&D, the number on the blades is a manufacturing date code system. I hope this answers you question.
I am not 100% confident that the person who answered the email knows what they are saying, but at least we don't really have to guess!