KK generally stands for KingKutter, a common and low priced brand of implements. They have a pretty decent website <A target="_blank" HREF=http://www.kingkutter.com/>here</A> and seem to be a great choice for low cost implements.
I've had a Caroni for couple of years with no trouble but the only thing in our soil is roots and an old stump now and then. Whatever you get, make sure it has a clutch and adjust it to YOUR tractor.