This $10 Nylabone Durachew has survived years of chewing.
This is a nylon bone I smear some peanut butter on, and leave with Nemo for ages. Nemo is a 120lb-or-so Great Pyrenees. He can chew through the cables that hold up the Golden Gate Bridge!
I knew nylon was tough but, wow! Might as well be steel.
Nylabone Dura Chew via Amazon
Image via Boing Boing