What is the MacBook air battery warrany?

What is the MacBook air battery warrany?
I have bought laptop batteries on ebay and yes, even the expensive ones are usually at very low capacity after only a few months. Ifixit has a vague clause about its battery warranty here: The iFixit Warranty

ANSWERS:

It's 1 year warranty on the iFixit battery. If it starts draining rapidly, dies completely, starts expanding those are covered under warranty.