It sounds like you're describing a 12mm Round LED Transparent Case Fan in Multicolor. These fans are commonly used in computer systems for cooling purposes and feature LED lights that emit multiple colors, creating a vibrant and visually appealing effect.

The transparent casing allows the colorful LED lights to shine through, enhancing the aesthetics of the fan. Additionally, the fan's round shape and 12mm size make it suitable for various computer configurations where space may be limited.

If you have any specific questions about this type of fan or need further information, feel free to ask!