Modern Mixing consoles use Insert jacks that allow you to break into the signal path to add an outboard signal processor (reverbs, delays, compressors, etc.) using just one cable, which connects to both the input and output of that device. The Hosa Cable STP202 TRS To Dual 1/4 Inch Insert Cable connects to your mixer's Insert jack (with the TRS end) and the Input and Output of your signal processor on the other end (with 1/4 inch phone jacks).