I bought this product to replace the transformer with a Sony infrared headphones from 1998 (yes, the old gear lasted longer!) Who just give up the ghost. As I needed 9V 100mA and can set the polarity, I opted for this model, especially as all the comments are positive. This transformer has operated for ten days without concern then the transmitter began to blink and light up intermittently. I have it examined by an electrician to see if it came from the sender. But it confirmed to me that it came in fact the transformer which does not deliver a constant amperage. It depends on the type of device you are using and also the electrical current in the area where you live.
