Review on L Shape 4-Pin RGB LED Light Strip Connectors: 10mm Unwired Gapless Solderless Adapter Terminal 💡 Extension for SMD 5050 Multicolor LED Strip (10Packs L-Shape Connectors) - Enhance Your LED Strip Lighting System! by Adam Hardy

This product is easy to use. It's a simple concept and the polarity of the product itself doesn't matter. You just have to make sure you connect the same polarity from one LED string to the other. In the process I had to double down all of my connections because the clips and small bits of metal that actually connect one string of LEDs to another simply weren't strong enough to make actual physical contact with the copper on the LED string. So I took two L-connectors, removed the clips from both, connected the two L-connectors together (one on top of the other, making sure they both go in the same direction) and then reattached a set of clips every end. After that, you are left with a set of clamps without an L connector. This will make the connection stronger, allowing small pieces of metal in the terminals to come into contact with the copper on the L-shaped connectors. I use the same concept with LED strips going into the other side of the L connector clips. I cut about half an inch of the LED strip off any excess pieces I have and then place them under the connector end of the LED strip (the part that goes into the L connector clip). Again, this makes the attachment tighter, causing the small pieces of metal on the L-connector clips to make contact with the copper on the LED strip. Connect two LED strips directly if you go in a straight line and don't need to turn the strip 90 degrees. The above worked for me. You might have better luck with these L connectors right out of the box.