....as i understand it, it is purelly cosmetic to the faceplate, the changes from the SST non C
are:
i) a 'milled' logo in faceplate
ii) no allen-bolts on front of handles of 19" er
iii) no rack mount holes on face of 19"....although it appears there are rack mount ears
behind the faceplate
iv) maybe the groove across front is machined differently now