It's a zippered pocket wallet you wear in your shirt.

It's a multi-use sports bra but they have many versions of it. Started on Kickstarter:

The entrepreneur bringing the Booby Pack to the Shark Tank in Episode 617 is Christina Conrad. She goes into great detail how the Fanny Pack for your Rack was first invented on a Kickstarter project ending January 2013. Christina set a $15,000.00 goal to fund her multi-purpose Sports Bra, which raised over $32,000.00 before Her successful campaign ended. How well does the Top Shelf Fannypack work keeping things safe and secure? I think this video used in the Booby Pack Kickstarter project demonstrates exactly how secure all your assets are when wearing this new Shark Tank product.  In the two years after successfully getting funded on Kickstarter, the Booby Pack has quickly grown into a full-fledged Brand selling fanny packs for your rack. In fact, almost 50,000 Booby's have liked this product on Facebook prior to this episode of the Shark Tank airing. (24,700 "Like's" x 2)

Although this product is considered a Sports Bra, most of the marketing has been for a Party Bra capable of holding all your assets firmly in place. Christina first invented the Booby Pack at an EDM Festival (Electronic Dance Music), and it was here She also found her target market. She claims if it weren't for the support from EDM concerts, the Booby Pack For Racks would've never grown into a successful product worthy of a Shark Tank appearance.

They ended up with a deal from Barbara.

Their believeinyourshelfie campaign is working.