Pentel Z3-1 Mechanical Pencil Eraser Refill - Set of 4

Only two out of the sleeve fit my pentel snugly. The others slip right out. Fail.

Good but this is the white version made in china not the gray Taiwan one you see in the picture

You can never have enough of these babies! Hard to find!

Sigh, right when the Sharp Kerry Green comes in stock this goes out of stock! I need erasers for my Sharp Kerry collection :P

Please restock :)

In short: These are dry, gritty, and leave a fine dust behind. Annoying and smudgy.

The only eraser refills I can find to fit my Alvin Draftmatic sold locally are these. I use them for note taking, so I like built-in erasers over block erasers and tend to go through them pretty quickly. The erasers that come with the pencil are a dream, and I'm sorely disappointed when I use one up because I have to resort to these.
These erasers are gritty-feeling, smudgy, and bad at what they're for. I actually found Jetpens while looking for the actual Alvin brand refills so I wouldn't have to deal with these anymore. These are precision-sized erasers that do not do a precision job. I have some Alvin Draftmatic eraser refills on their way to me now. If they fit my pencil like they should, I'm never touching these again.