200PCS 10Value Crystal Oscillator Resonators Assortment Kit 4 MHz, 6 MHz, 6.5536MHz，8 MHz, 10 MHz, 12 MHz, 16 MHz, 20 MHz, 24 MHz, 27.145 MHz

I had use 2 pairs to replaced my kid radio controller and they worked. I do recommend this product.

This is a handy set of crystals for your electronics workbench, for building any electronic projects that involve generating a clock or other oscillator at these frequencies.To validate that they deliver as specified, I did a simple test with my NanoVNA to find each crystal's resonant frequency for the 4, 6, 8, 10, 12, 16, 20, and 24 MHz crystals. Bearing in mind that my NanoVNA's own oscillator runs a little "sharp" so the actual frequency it outputs is a bit higher than indicated, (I'd estimate about 250ppm), the eight crystals that I tested all showed up right on their marked frequencies.

There are a lot of good usable oscillators here. Some of the caps have the numbering worn off and the legs are a bit thin but they work pretty well!

Nice assortment of many of the common sizes need to clocking circuits. This is a great set to have on the work bench.