If you want to know the right answer you should attach an options to choose. Anyway I think the right answer is USB flash-drive. It's possible to create recovery on usb and store any type of files.
I would answer, but there isn't enough information to answer for. .
Answer:
1000
Explanation I SEARCHED IT Up
Haven't used earsketch, but here we go.
Answer:
1). Make a track in earsketch, make it like 6/7 seconds
2.) export your track as an .mp3, .wav, or .ogg (your choice!)
3.) (If on android) Navigate to settings, now search for an entry for ringtone.
4.) If you have no luck, look up how to set ringtone on your desired phone brand (iOS, Android, etc.)
5.) Test out your new ringtone
6.)Profit