Green gecko hide is a miscellaneous item in the Fallout: New Vegas add-on Honest Hearts.
It is found on dead green geckos. This item can be turned into a tanned green gecko hide at a campfire if you have a survival skill of 70, greatly increasing its value to 300 caps. It requires:
Also, with a Repair skill of 50 it can be turned into 7 leather belts at a workbench.
It looks exactly like a golden gecko hide in game.