Review on Homemory 10pcs Submersible LED Lights with Remote Control - Waterproof EFX Lights for Vases, Showers - Battery Operated Color Changing Underwater Lights for Easter, Halloween by Ivan Cantrell

I bought these to complete my daughter's robot princess Halloween costume, lots of color options, all batteries work right away. Turns out you have to tighten them by screwing them together VERY TIGHT. I mean it's a lot harder than I thought. Otherwise, the battery and the LED will not touch and there will be no light. They are well made and durable so you can really use them as needed. No scams, just useful advice.