u/Healthy_Role9418

Question for the fellow scrappers. I've had the opportunity to remove all the piping from a house being demolished near me. I've never dealt with pex piping before, and my question is, are the bands placed around pex piping to secure it to a valve, joint, elbow, etc., copper or red brass? It looks like it could be either and filing it isn't a persuading one way or the other. Just want to sort and classify it correctly. Thanks for your help!