Crystal Harris's engagement ring from Hugh Hefner. Credit: Crystal Harris

Crystal Harris is no longer keeping her engagement to Hugh Hefner a secret!

The Playboy model showed off her massive diamond ring on Twitter Monday -- from every angle.

"My beautiful ring from Hugh Hefner," Harris wrote with collage of three photos of her new bling. The engagement ring feature a large round diamond with smaller stones covering the entire band.

On Dec. 4, Us Weekly confirmed that the Playboy founder, 86, and Harris, 26, picked up their marriage license from the Beverly Hills courthouse. The two became engaged in December 2010, but Harris called off the wedding in June 2011. One year later, Harris revealed on Twitter she had reconciled with Hefner. 

Hefner's ex-girlfriend, Bridget Marquardt, confirmed the couple's engagement (and new wedding plans!) to E! News on Dec. 6.

"Hef has a wedding in the works again," Marquardt, 39, revealed. "I just hope he's happy. I'm happy for him if he's happy." Though she won't be attending the nuptials, Marquardt added, "And New Year's Eve is a romantic time to get married. It's a romantic holiday. A good way to start off the new year."