Multi-color Printing Nozzle
The price is for the Nozzle only. It's a nozzle, thermal core integrated as shape Diamond.
Not includes thermal tube, heater cartridge, thermistor, heatsink or other parts of 3d printing.
Diamond Nozzle is designed for multi-color printing which is using 1 nozzle to achieve.
There are ways for multi-color printing:
1. Splendid color 3d printing filament
2. E3D Kraken multi-nozzled hotend
RobotDigg Diamond Nozzle
Instructables adding more extruders to any 3d printers using Diamond Hotend