BlackSmith strings impress with the high quality of their coating. BlackSmith coats the entire string and not (like most other manufacturers) just the winding wire, which successfully prevents dirt deposits between the grooves of the winding and thus guarantees a significantly longer durability compared to other strings. There are two different types of coating, which the manufacturer calls AOT and AAOT, and which differ primarily in the thickness of the coating. The individual advantages of the two coating types are listed below. In addition, the non-wound strings of the AOT and AAOT sets are subjected to a special cold treatment called "Sub Zero", which gives these strings a significant plus in tear resistance. Significantly longer durability than non-coated strings. Cold treatment "Sub