The Flame Penguin Flippers are a third-tier piece of armor, as you have to kill and shear Flame Penguins before crafting them. They are like the Penguin Flippers, but are even faster in water. In some cases, however, it is hard to control your swimming while wearing them. Note that these flippers still slow your walking and jumping speed on land, and this effect can only be prevented by wearing the Flame Penguin Leggings (and not the regular Penguin Pants).
The Flame Penguin Flippers can be repaired with Flame Penguin Scales.