Chikuma Seisakusho chikuma Audio Board for Power Tap TB400 Used item. Body only. No pets, non-smoking environment. We would appreciate it if those who understand used items would purchase. The TB400 is a power tap dedicated board compatible with all Chikuma power boxes, featuring the high rigidity of the strongest aluminum alloy A7075 with a 15mm thick material, Chikuma's unique vibration damping structure, and the latest special electromagnetic field treatment to further enhance vibration damping ability. Evolution from 75TB-350 to TB400 [Improved Rigidity] While 75TB-350 used 10mm thick A7075 material, TB400 uses 15mm thick material to further increase rigidity and improve the vibration damping ability of the unique vibration damping structure. [Latest Special Electromagnetic Field Treatment] The special electromagnetic field treatment of 75TB-350 has been updated to the latest special electromagnetic field treatment, further improving sound quality performance. [Adoption of C-chamfering] C-chamfering is adopted on all four sides to further enhance the effect of the unique vibration damping structure, realizing further improvement in sound quality performance. Vibration Damping Structure Vibration damping structure + latest special electromagnetic field treatment Using the strongest aluminum alloy A7075 single plate 15mm thick material, inheriting the unique vibration damping structure such as a round hole in the center and 0.6mm slit processing from the short side toward the center, which is also a specification of 75TB-350, and incorporating a new special treatment, further improving the vibration damping characteristics, and enabling the power box to be used in the best environment.