T6s 6.3 stereo phono plug One hundred percent technology: The ViaBlue™ T6s series. ViaBlue™ T6s phono 6.3 stereo plugs have contact pins made of bronze which are 24 carat gold-plated. The shells are made of aluminum. Cables up to 9.5 mm diameters can be installed. All connectors of the T6s series are supplied including two diameter decreasers. Those diameter decreasers make an assembly of cables with small and big diameter possible and grant a firm strain relief.