Billie Eilish is teaming up with Fender to release her own signature ukulele.

It’s the first instrument Billie learned to play at just six years old. And in a promotional video, she revealed the first song she ever wrote on the ukulele was about going outside to play while singing, “What a wonderful life for us.”

Billie also explained that after learning her first three chords, she knew how to play 20 songs. She explained, “It shows you how simple songs are.”

Billie’s Fender ukulele retails for $299.99. Check out the video below: