The Nationalist Forces that regulary face off against the Federal Army lack the manpower that their enamy can field. Therefore they have developed heavily armoured mobile power suits, each capable of taking on several units of regular Federal infantry by themselves. These power suits are capable of travelling through the roughest terrain and performing hit and run operations against Federal facilities and supply lines.
I picked these little Gundam figures up from ebay from a seller based in France. I'm not sure what scale they are, but they fit really well alongside 15mm figures as large power armour suits.