Please note that the price is for 20 pieces of the APA102 2020 size LED

These are extremely small and nearly impossible to hand solder. You will most likely need to make a custom PCB and use solder paste in order to use these.

The popular WS2812B LEDs require very precise timing of data signals, which is a problem for many small or low power microcontrollers (ie. The Digispark and the Adafruit Trinket) or for WiFi and Bluetooth development boards (ie. The ESP8266 and nRF51822) that interrupt the data to the LEDs when they have to do tasks related to maintaining the wireless connection.

The APA102 has a second data pin for the "clock" signal, which essentially lets the microcontroller control the timing. That means that if the transmission is interrupted, the LEDs will wait to receive the remainder of the data packet.

These LEDs also have a much higher PWM frequency which results in a better color reproduction and less flicker.

This article gives a more detailed comparison.

Eagle Library

You will receive a bag with the total number of LEDs you have ordered, possibly on one or more cut-tape strips.

If you are interested in larger quantities than I have available, please contact me. I can usually get them from my supplier in under a week.