How to COMPLETELY RESET iPhone 5 with no iTunes?

Okay, so I found an iPhone 5 recently, in somewhere you won't believe… The garbage. It's really beat up, but still functional. I saw it when I was taking the trash out, only to find it's disabled and the lock button doesn't work so I can't reset it from iTunes. Is there any way around this or should I just put it back where I found it?

Settings-general-reset-erase all content and settings

Your gonna have to plug it into iTunes away. It will say it's disabled and then you will have to put it into DFU mode then restart it from there. It's pretty simple after that.