Trolls Sing Along Boombox with Real Working Microphone Rock N Troll: Rock out and sing like a star with your very own Trolls sing along boombox. Microphone: Sing your heart out with the real working mic. Built-in Music: Sing along to built in music from Trolls. Listen to fun phrases from Trolls as well. Connects to MP3: Plug in your MP3 player and listen and sing along to whatever you like. Perfect Gift- This will make the perfect birthday present or gift for anybody who loves Trolls, singing, and music. Let your little Troll shine.