It looks like a Zaku II... but I'm not sure which Zaku II it is... so, uh, halp?

Edit: Antennae Horn indicates it's a squad leader/commander unit of some kind... hmm...

Edit2: Okay, shape of chest indicates it's not a Kai or F2... so just a regular Zaku II S(Commander)-Type? The same type Char uses?

Edit3: Next page confirms it's an S-type (read it earlier but for some reason it didn't click for me...). And that it's using a Gelgoog shield.