Iwako Japan is transitioning from the old style cardboard header card stapled to a plastic bag to a new all plastic rip and grip plastic package. The top green card is from a koala Japanese eraser package. The brown is the top part of the rip and grip package that will be used for the upcoming Forrest Fellows Japanese erasers.
The new bags are called rip and grip as they have an adhesive flap on the bottom of the bag, which you can not see here. There is a thin plastic protective mask over an adhesive strip. The mask is peeled off and then the flap is folded over and pressed to seal.
We suspect that Iwako Japan went to these bags as Japanese erasers can be inserted and the bag sealed quicker than the cardboard header card Japanese eraser bags.