Production date of a rubber

[Hamasaki_Fanz]

Hello guys, I want to ask something:

How do we identify the production date of a rubber (especially DHS rubbers) ?

I ask this because im afraid of getting an old rubber (2-3++ year-old rubber) when buying one.
Maybe ChenChen/any DHS users can help me on this?

Also if know how to identify the production date for other brands please mention below. Thanks