They are produced by KW but unlike the Eibach Inox Kit (which are KW V1's) the used materials for Weitec are cheaper.
Basically they are the KW V1's but without the stainless housings (and from what I've heard they are a bit softer and more for street use only).
A guy that owns a set told me that the quality is good but service/warranty is notoriously bad. Seeing the small price difference with KW I would go for the V1.