The Keysight 11904B is a metrology grade, 2.4 mm female to 2.92 mm female adapter with dc to 40 GHz operation. It is 16.3 mm long and has a diameter of 8 mm.

• connector type: 2.4 mm (f), 2.92 mm (f)
• return loss: >24 dB
• repeatability: -40 dB
• electrical Length: 11.3 mm (0.45 in)
• overall Length: 16.3 mm (0.64 in)
• diameter: 8.0 mm (0.31 in)