Premium upgrades and earlier than the new good place to be， Premium Edition， more power， more muted， with a few hundred dollars using the same mouse button thousands of times shrapnel and wheel encoder， feel better， generally two buttons and scroll wheel -4 years not bad inside the crystal and IC are enlarged (double panel settings) is different from the market generally only add a layer of the panel up (not double-sided) see the following figure:

 

 

             有线实物拍照如下：