DISCLAMER: This is not my skin, it is created by Crazy-G. It was made by him for the Community Medevial Update.
Since the Equalizer split basically broke every equalizer skin under the sun, I'll write a mini guide here on how to convert old equalizer skins/current escape plan skins to the equalizer.
Step 1. Download any old equalizer skin that was broken (aka only works on Escape Plan now).
Step 2. Unpack the skin into your /tf/ folder.
Step 3. go to /materials/backpack/weapons/c_models/c_pickaxe/ and change any files with c_pickaxe in the name to c_pickaxe_s2. DO NOT change the folder name to c_pickaxe_s2.
Step 4. go to /models/weapons/c_models/c_pickaxe/ and do the same thing, changing all c_pickaxe in the name of files to c_pickaxe_s2. Once again, DO NOT change the folder name to c_pickaxe_s2.
There you have it. Start your TF2, and your equalizer skin previously broken by the patch is now fixed.
TL;DR: c_pickaxe files are for escape plan c_pickaxe_s2 files are for equalizer if you are converting a pre-split equalizer skin to new equalizer, do not rename folders.