Yong Ju Ji

3 Patents

• US121373112024

  Earphone with Duct Unit Dividing Pressure Equilibrium Hole and Back Hole

  EM-TECH Co., Ltd.

  0 cites
• US116960592023

  Two-way Receiver Having Front Bass Duct

  EM-TECH Co., Ltd.

  0 cites
• US115640262023

  Earphone Having Pressure Equilibrium Structure

  EM-TECH CO., Ltd.

  0 cites