(CNN)Britney Spears is jamming out to music by none other than her ex, Justin Timberlake.

Spears posted to Instagram a video of herself dancing to Timberlake and Jay-Z's song, "Holy Grail," and even tagged her ex in the post. She captioned it, "Danced in my black (turtle emoji) neck last week to HOLY GRAIL !!!! I KNOW ... turtle necks are SO ME ... !!!!"