Neutrik Miniature Transformer Balancing Adapter

Neutrik NA2M-D2B-TX Miniature transformer balancing adapter.

3 pole XLR male to RCA

From the manufacturer:
Low cost solution for unbalanced/balanced line conversion and passive DI applications, where no earth or gain switching is required

Audio transformer 1:1
Impedance ratio: 200:200
Source/load impedance in Ohm: 200/2k, (600/10k)
Max. Input level (@ 50 Hz, 1% THD): -3 dBu