One Drop pads do not fit most yoyos. That is, if you get their “main” pads for the OD yoyos. The ones they just call “Flow Groove” pads.
Confusingly, they do make pads for other sizes, and call them “Flow Groove” pads also… but these will be marked as 19mm OD slim pads or something similar.
The 19mm OD pads I got were slightly “short” for most grooves. I LOVED that for yoyos that were snaggy, but for other yoyos it made them lose a bit too much response.
I’ve never had any problems with plain ol’ white silicone pads like the kind you get from YYF.