... .22XT 3.51.0mm voice coil Features of the loudspeaker kit: 1. It applies to home theatre system, professional audio ... designed according to client’s requirement.Specification of the loudspeaker kit: Model NumberZJ51T172R-PVVC Diameter51.0 mmVC Bobbin MaterialKSV/NSV/ ... of specifications ,including silk ,POLYESTER, ALUMINUM, TITANIUM, MALAR ,PEI, PEN AND PU diaphragms and dust caps,ranging from 13 cores ...