如何区分 Beoplay/Beosound A1 的版本？

Beoplay A1 包括了一个 USB-C 充电接口以及一个 mini-jack 接口。指示灯位于扬声器侧边。

Beosound A1 2nd/3rd Gen 包括了一个 USB-C 充电接口，产品指示灯位于扬声器顶部。 

外观区别 

Logo 标
Beoplay A1
Beosound A1 2nd Gen
Beosound A1 3rd Gen

按钮布局
Beoplay A1
Beosound A1 2nd Gen Beosound A1 3rd Gen

如何查找产品的序列号：

Beoplay A1

Beosound A1 二代

Beosound A1 三代