HOSA CMP-159 Stereo Breakout, 3.5 mm TRS to Dual 1/4 in TS, 10 ft - CMP-159
This Hosa Stereo Mini Male to 2 Mono 1/4" Male Y-Cable is a "Send Return" cable (also known as an Insert Cable), conventionally wired: TIP = Send, RING = Return. It can also be used as a "Y" to split stereo signal into Left and Right. In this case, Right = RING and Left = TIP.
It can also be used from your phone or computer's headphone output to connect to a mixing board or powered speaker.