1)Best high boronsilicate glass tube 2)Germany magnetron-control sputterin Film Plating Machine. 3)skilled work
Trifire vacuum tubes are coated by three layers in the inner tube. One lay is reflection reduction layer, one is absorption layer and the third layer is infrared layer.Trifire tubes is produced with three layer porcelain new technology of stainless steel, red copper and aluminum nitride with the sputtering controlled by a three butts magnet. Trifire tubes can quickly absorb heat, and its heat preservation ability is quite good.