This is a string of 20 domed LED modules, each containing one WS2811 controller IC and three bright RGB LEDs. The string runs on 12V and works with all the WS2811/WS2812 controllers and code out there. They're great for higher brightness applications, and 12V is a handy voltage for mobile use. I used a string to light up a mobile DJ booth; speakers, Arduino, lighting, etc all powered with a 12V deep cycle battery.
The domes are about 30mm diameter, and the cables between pixels are about 100mm long.
These items are new and expected to be in fully working condition.