inputs.text: german engineering finest - purchased head unit replace factory stereo 01 chevrolet silverado 2500 impressed alpines products even bought unit fact everything systehem made alpine except 1 farad capacitor picky music sounds played pleased way head unit sounds many inputs output configurations application music usb bluetooth aux etc however like many companies not modules included systehem bluetooth sirius radio input happy picked head unit systehem definitely continue buy alpine products quality product sound