Maximum Armor is a pokemon specific item for unevolved pokemon that gives 1.5x boost to defenses to the specified pokemon. Eg. Maximum Armor Scyther gives Scyther 1.5x to Def and SpDef.
Additionally a pokemon holding the appropriate ME stone can ME evolve which is basically Mega evolution for unevolved pokemon. ME Evolution gives about +80 stats rather thr +100 of mega evolution.
ME Scyther gets +60 to Atk and +10 to Def and +10 to SpDef (the defense stats still are 1.5x), and becomes Bug/Steel like Scizor.
by imdfantom