This upgraded A05 uses an efficient and stable TPA3221 amp chip,QCC3034 Bluetooth 5.0 Stereo Audio 2.0 Channel Amplifier Receiver,The max output power can reach 105W*2 (under 4Ω load).Small simple compact design but practical and powerful, this A05 Hi-Fi Bluetooth wireless amplifier exclusively designed for the customers who pursue HiFi sound; All parts and components of this product are original products, unpretentious and pure in quality;