Pentatonix - Britney Spears Medley - Sing Off - Series 3 - REACTION!

Original Video:    • 6th Performance - Pentatonix - Britne...  

The sang Britney Spears songs of "Oops I did It Again" & "Toxic" & "Hold It Against Me"

Pentatonix (often abbreviated as PTX) is an American a cappella group consisting of five vocalists originating from Arlington, Texas.[3] Their work, which is mostly in the pop style, consists of covers of existing songs, sometimes in the form of medleys, along with some original material. Their music is defined by their own arrangement style, a strong presence of low bass vocals, and a diverse range of vocal percussion.

Pentatonix formed in 2011 and came to prominence the same year by winning the third season of The Sing-Off on NBC, their victory earning them $200,000 and a recording contract with Sony Music.[4][5] After being dropped from their label (Epic Records) after The Sing-Off, they formed their popular YouTube channel and distributed their music through Madison Gate Records, a small independent label owned by Sony Pictures that distributes movie soundtracks.[6][7][8] They also made effective use of social media to interact with their fan base.[9] Having now eclipsed 8 million subscribers and more than 1 billion cumulative views, the PTXofficial YouTube page is currently the 14th most subscribed-to music channel and the 51st most subscribed channel overall, while two members, Scott Hoying and Mitch Grassi, also have their own comedic YouTube web show, Superfruit, with over 1.4 million subscribers and over 132 million views.[10][11][12] Pentatonix's music video tribute to Daft Punk recently surpassed 145 million views.