Would have to agree with another reviewer who discovered that the 3.5mm or 1/8" stereo Jack is slightly oversized and can cause an intermittent connection on the inserted plug tip. Also, the Left and Right RCA plug connections are not marked.
Sound from my speakers seemed heavy on one side, so I listened closely and discovered that signal was getting through only one channel. I swapped out a 6-inch cable adapter and verified that the problem was with the 3.5mm Stereo Jack to 2 RCA Plug Splitter Adaptor. While I like the compactness, obviously the malfunctioning is unacceptable. I would ask for a replacement, but I can't find this item in my large set of past orders.
CONS: Lack of channel label is an annoyance. RCA plugs fit is loose. The major problem: Signal passed through only one channel.
Very good, simple device that needs some proper marking.
PROS: Properly merges two RCA type connections to one stereo 3.5mm jack.
CONS: The left and right sides aren't marked on the RCA side so it's a 50/50 shot on whether or not you get it right the first time when setting up. I figured it out and marked it. Recommend Monoprice put SOMEthing on these to mark at LEAST one of the sides.