The document describes four portable Bluetooth speaker models - DY20, Sport 1, DY22, and Sport 4 - from the company Szdoubleseven.com. The DY20 has a 4000mAh battery, aluminum alloy enclosure, and two 5W loudspeakers producing rich sound with good bass. The hottest selling DY22 has a 2000mAh battery, two 5W loudspeakers, clear sound with good bass, and a low factory price. Both the Sport 1 and Sport 4 have 9 hour working times, are waterproof, produce rich sound with good bass, have 20m transmission ranges, and utilize ISSC solutions in their unique designs. Contact information is provided to request a price list.