Any warranty on their parkas? White flakes are coming out of metal sprockets from elastic clinchers.

Yes

The staff at the store on Newbury street are very helpful when you bring in gear to be repaired. They will either send jt to a tailor in Boston or out to Reno where the repair shop is for Patagonia. If you can live a week kr two without the gear i highly recommend taking it into the store.

All Patagonia items have life time warranty. You can fill out an online form to ship them the item in question. They'll fix and ship it back to you.