Hello Nathan,
Considering that this is not an NI product, I would recommend you to contact the manufacturer or the seller for a better description of this frequency transducer.
Looking at the general description, it looks like this frequency transducer provides a DC voltage output proportional to the frequency value of an input signal. However, without a datasheet of a specific model, it could not be determined the range of frequencies that can be measured, the range of the output, or if there is a linear relationship between the input and the output.
Regards,
Gustave
