These are General Electric made-in-Syracuse devices that we have sorted for creating noise in Zener mode. Test conditions + 15V through the device to a 1 Meg resistor to ground. Under test conditions, we guarantee 100 mv. p-p unamplified and no snap-crackle-pop. A typical basic circuit is here. The second transistor can be any common NPN device like a 2N5088, and it does not have to be sorted.
Special Note: We can't discount for quantity because of the hand-sorting. If you use this kind of device for production, please buy bulk of SKU 2001N11 and sort your own. Those will be raw, unsorted devices.