EIJU BEa-160.4 4ch amplifier。DS18 Compact Full-Range Class D 4-Channel Car Audio Amplifier。SoundExtreme by ECOXGEAR 4- Channel Amplifier。仕様周波数特性 10Hz~28kHz定格出力 40W×4(4Ω)外形寸法 (W)440×(H)53×(D)240mm製品の案内は以下もご参照ください。DS18 ELITE ZXI.4 Full-Range 4-Channel Class D audio power。https://eiju-corporation.jimdo.com/amplifier-history/