NATO wiring for comm equipment

[Endymion]

I've tried Googling and thus far the only results I've managed to find for "NATO wiring" and any variation including "standards" and "configuration" have been for product.

Can anybody explain what differences there are between products using NATO wiring standards and those without? I'm looking at Peltor products specifically. Aside from requiring use of a similarly wired PTT and comm piece, what should I know about NATO wiring before purchasing? It seems that most of the interesting items on eBay are NATO configured.