2x2 Square Matrix WS2812B 5050 NeoPixel 4 Way Serial RGB LED with Integrated Controllers
WS2812B Neopixel Matrix - 4 Pixels
A super-bright WS2812B (aka Neopixel) Square Matrix with smart RGB LEDs
Data in is timing-specific so you will need to use standard Neopixel code.
Dimensions: 15 x 15mm