Universal DC Socket 5.5 x 2.1mm to Plug connector size 5V 7.83HZ Schumann Resonance Low Frequency Pulse Wave Generator Audio Resonator. Features: 5.5 x 2.1mm Jack to 8 Plugs. 1 x 8 Plug One Set. Steel Watch Case Remover Cover Opener Screw Back Wrench Watchmaker Repair Tool.
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