There are a couple other threads about the new and old filters and apparently you can't always tell them apart just by the presence or absence of a tab. I don't have any Hairo filters but would be happy to send you a few other brands (Chemex, Trader Joe Melitta-style, and some weird Japanese brand that I got some years ago) if you want to test those. I know some people use Chemex filters in V60 cones.
There are a couple other threads about the new and old filters and apparently you can't always tell them apart just by the presence or absence of a tab. I don't have any Hairo filters but would be happy to send you a few other brands (Chemex, Trader Joe Melitta-style, and some weird Japanese brand that I got some years ago) if you want to test those. I know some people use Chemex filters in V60 cones.
Ah that's a bummer. Thanks for the offer though!