Brand New Genuine JBL MR802, g730, G732 Corner.
These are the 90° corners. They work for many different models but you might want to replace the entire set for aesthetics or to complete the interlocking faces if the cabinets are being stocked. They replace the old gray corners with the embossed logo which have been out of stock for years. You can see a comparison with the new 73393-011 corners and the old gray ones below.