What does Set E strip tag mean?

[Swoboda4]

I'm sorry but I don't remember what strip tag "Set E" means. Anyone know? I searched on our forum and I didn't see anything, but I know it was discussed somewhere. And it's in reference to 2004 Mets jerseys. Thanks
By the way is it me or is Cespedes using a new unbroken-in oversized glove every game ( practically) and is this contributing to the ball popping out regularly??

[metsbats]

Robert

I was told that Set E were Extras. Most call ups or new players typically had set E jerseys. However you may see players with the team all year issued set e especially in a year like 04 when the Murphy patch was put on late in the season.

[Swoboda4]

Thanks David. I've also quickly started a collection of game used baseballs and my own way of documenting their short existence. I guess there's no end to this hobby even if you wanted to escape.