Shure 330 Uni-Ron

This model was originally marketed as the Unitron, and later renamed Uni-Ron, losing the T and gaining a hyphen.

A discussion at the Coutant website suggests this could have been due to trademark infringement with the telescope manufacturer of the same name.

Manufacturer Specifications:

• Frequency Response: 30 to 15,000 Hz,
• Impedance Selection: Switchable choice of three low impedances; 50, 150, and 250 ohms
• Built-in Shock Mount
• At 19 to 300 ohms. The microphone output shall be: 50 ohms -59.0 dB
• -58.5 dB (0 dB 1 milliwatt per 10 microbars)

Official Shure data sheet for the model 330.

A post about the 330 at the Coutant Website.