This auction is for ONE Altec 15356A audio transformer. There are multiple units available. 150:600 ohm primary to 600 ohm secondary. The photos are representative of the unit you will receive. The frequency/phase response graph is for a typical unit, wired for 600 ohm primary; the signal level was +4dBu, and output was terminated with 15k ohms (Terminating the secondary results in a flatter high frequency response, with 15k termination the frequency response is essentially flat and the input/output gain is unity). All transformers will be tested before shipment and are warranted to be fully functional. Returns will be accepted for replacement within 14 days.