Thanks OneHundred80! Yup, looks familiar. My pulley is definitely aluminum and I probably have about 10K miles on it w/o issues. This is frustrating because I didn't spot it earlier. Oddly, there is enough of the connected pulley to run the supercharger. It performs as usual but now it's parked until I can get a replacement. I am confident that EC will make it right. Maybe I need to find a steel one. This could have thrown the belt off and caused damage under the hood. I guess I DID catch it in time.