What iteams do you make the most money on.??????????

Just sitting home and thought this would be a interesting tread to start. We have a very diverse community here from all across the U.S.A. and abroad. We make our most profit from scrapping commercial and industrial Air conditioning units, just wanted to see what other guys on here have to say please don't tell us copper in a pure copper form, what you do to get your copper would be more along the lines I am looking for just using copper as an example. Here are a couple of units we have scraped. This could be interesting.1956