Product Description UNIT MODEL: KTS 1687 SPECIFICATION: Wireless Transmission Rang: 10 meters Speaker Drive Size: 4 inches Output Power: 10W Frequency Response: 100Hz-20KHz Signal to Noise Ratio: >85dB Charging Time: 2-3 hours USB Charging: DC5V Product Battery Capacity: 1800mAh MIC Battery Capacity: 500mAh Max Memory Support (USB/SD): 32GB Play Time: up to 1-2 hours at 75% Volume Product Size: 18.5*14.5*18.1CM