Pick-up Pet Upgrade
From FlyFF WIki
Cost: 600 gPotatoes
Info: This powerful magic spell tranforms your normal Pick-up Pet into a Special Buff Pet. You must have your Pick-up summoned when attempting to use this spell.
Extra: This item will not fail when used. It will give your pet 2 open slots, to get more slots you will need to use Keys. It will also make any pet that is mailable (GM reward, pets from special boxes) unmailable.