1. Computer Speaker 2.Compact capsule design 3.High quality 4.Built-in rechargeable battery 5. ... USB speaker2.Digital USB 2.0 Speaker Systerm2.The special innovative design of extendable bass chamber used-the chamber can be expandedto ... high purity4.Interated ,readily achievable volume control switch5.Lightweight, compact design for easy transport6. Hamburger shape,with the bass chamber opened ...