Britney Spears re-releases 2016 song 'Mood Ring'

May 29 (UPI) -- Britney Spears has re-released a rare 2016 song.

The 38-year-old singer released "Mood Ring," a song from the Japanese deluxe edition of her 2016 album, Glory, on Thursday.

"Mood Ring" is produced by DJ Mustard. Spears celebrated the re-release by sharing a new album cover for Glory on Instagram.

"Repurposed this since we didn't use it... You folks wanted a new album cover..... ta da there you go!!!! What was requested next is out now," she wrote. "I hope you turn #MoodRing up sooooooo loud!!!!"

Spears' fans helped send Glory to No. 1 on the iTunes Pop Albums chart this month. Spears thanked fans in a video May 3.

"I just figured out that Glory went to No. 1 on the iTunes charts. I have no idea what happened. Because of you, I am having the best day ever. Thank you guys," she said.

"Mood Ring" is Spears' first release in four years.

Spears is self-isolating at home amid the coronavirus (COVID-19) pandemic. She shared in a video in April how she accidentally burned down her home gym in 2019.