What essential spares do you carry - I now have spare wiper blades !!

Went to start yesterday front wipers came on and passenger blade just flew off - it broke, couldnt re-fit !

Must have been a duff fitting - got it fixed under warranty no problem, but got me thinking. If it happened on the drivers side and it was lost - you'd be stuffed. Not the sort of thing you realise can be a show-stopper until it happens. Not sure LR assist would sort, so bought 2 spares.
Just in case ! Its a bit like having the spare tyre - a comfort knowing you can continue.