A photo of an EvoX head from LeLutka.
EvoX is the name of a UV mapping developed by LeLutka for mesh heads. They felt it was an improvement on Evo which used the standard UV mapping from Second Life. The EvoX mapping has grown in popularity and is now offered by other creators of mesh heads, such as Akeruka, Catwa, and others.
Generally, if skins or cosmetics say they will work with LeLutka EvoX heads, they will also work with EvoX heads from other creators.
The products below are examples of heads that use the EvoX mapping, though this isn't an exhaustive list.