The basis for SPRENGER dog collars made of black stainless steel is provided from the well known polished stainless steel product and exposed to a thorough galvanizing process.  Only the upper layer of this material will be colored so that the inner-material still consists of bright stainless steel.  Depending on the nature of the fur and the usage of the dog collar it is possible that abrasion wear on the black upper layer will occur at different times.  The brighter metal underneath will appear gradually and an “antique look” occurs.

The quality is not affected by this visual change.  Slight color deviations from batch to batch are also possible from the manufacturing process.