My model is K1-3I9, I am a former Imperial protocol droid. From what I've been told, I used to be used as an early unit to communicate between the Hut crime family and the Imperial empire, negotiating a suitable Peace between the family and the empire. Of course my model was found to be defective. It is not that we didn't do our job of translation, it's that we where incapable of pleasing the huts for long... They where fickle and quite often hit and destroyed the units when mad. So the empire had to replace us with a more resilient model.
During the war the rebellion had decided to scavenge old models of droids for parts, working units, and possible info. I was one of the droids they Reprogrammed to work with them
I am actually not entirely my original model. The original K1 model was built to be cheep and easy to make. Of course we where also more expensive, with highly advanced translators, which is why the Huts breaking us was so costly. I have had my translator downsized and I was given several after market modifications. I have telescopic arms, with free moving joints, unlike the original K1. My sensors are also upgraded and I have consealed compartments in by body.
Since I was Reprogrammed, I haven't really done much. I've been put to work interpreting the Hut language, and been "trained" to help in the case of an attack on a rebel base.