speaker cooler backpack 1.Favorable price 2.Any colors and size are available 3.Quick delivery 1, Product Information: Product Name: speaker cooler backpackFabric: 420d NylonSize: h 40 x w 14 x l 28 cm, also to be customized Logo Options: Silk Screen Printing ; Emboidary ; Rubber patch, etc...Parameters:Speaker diameter:57mmAUX input impedance:10-20KΩ output impedance:4ΩFrequency range:80Hz-20 ...