Coin-sized bluetooth speaker: the smallest wireless speaker in the market with a diameter of 1.4-inches and weight of 2.46 oz, it boasts an exceptional stereo sound quality that you won't expect from a miniature speaker. Pair it easily with your smartphone, tablet or music player: the u mini speakers supports bluetooth version 4.2 and instantly pairs with most bluetooth enabled devices. Four hours playback time for your playlists: outfitted with a 400mah battery, the u mini speaker transitions from a stationed speaker to a portable speaker you can use to play your favorite tunes on the go all Summer/year long. Complements your digital life and gadgets: the u mini speaker is a stylish bluetooth speaker bundled with a remote shutter and microphone; use the built-in remote shutter to capture wireless selfie shots; the speaker also features a built-in microphone for hands-free calling. Metal shell (aluminum shell), net cover, horn, pcba board, bottom cover, silicone pad.