Lava Waders

Lava Waders allow you to walk on water and lava, give immunity to fire blocks, and give you seven seconds of lava immunity.

The lava immunity effect stacks with Lava Charm for a total of 14 seconds.

Simply standing on the lava does not begin the "burning countdown", making it completely safe to do so. This only happens when you dive in.

Bugs
When running from ice blocks straight onto water or lava, you will continue to slide when you try to stop. Unknown if this happens with the regular Water Walking boots.

Tips
These are very beneficial when killing the Wall of Flesh if you do not have Water Walking Potions or when mining Hellstone.