Amplify your phone's mp3 music or speakerphone via analog horn with this convenient Green Acoustic Boom Phone Speaker & Stand featuring a compact silicone holder in a colorful building block design with a slot to hold phones vertically or horizontally, an analog horn that amplifies the volume 4 times and an additional slot in back for inserting charger. For iPhone and smartphones. No external power needed. Washable, durable, portable and waterproof. Comes packaged in a blister pack.