Help ID motor encoder

Hi,

I have this motor encoder that was purchased off ebay. It did not come with any information in terms of pinouts. I assume it is some kind of quadrature encoder. The two slot sensors don’t have any optics or holes where an led could be placed that I can see.

Can someone help me identify what kind of sensor this is? Maybe perhaps help me with the pinout identification as well. Assuming it is a quad encoder, there should be 5V, GND, pin A and pin B. Thanks.