Beater

An object/item you use freely, recklessly, and commonly, to avoid damage to an identical/similar version of that item that is newer or superior to the "beater" item.

Dude 1: "hey bro, lets go out to some trails on our bikes, its gonna be very messy cause it just rained out, so it'll be all muddy"

Dude 2: "yeah sure! let me just put on my beater shoes, along with my beater bike, to make sure my new jordans and my schwinn bike don't get fucked up."