3/0 ST-66 are the size that come in the box I believe. I use 4/0 and 5/0 ST-66/76 on my Komodo and I keep the Wombat at 3/0 because the bigger sizes will catch each other as they are too big for the Wombat.
2/0 must be pretty small and short then, maybe good for x-raps. probably stick to 3s and 4s, buying a bunch with gift card
4/0 or 5/0 size hooks will change the action of the poppers. We tested all our poppers to float correctly. OTI sea dragon will come with 4/0 Owner ST-76 hooks and size 11H split rings.