The Hotend is the business-end of all German RepRap 3D printers. It is also the most likely area to get clogged or damaged.
If you need a replacement (or a spare), simply select your printer model. Please note that there are different hotends for the various German RepRap 3D printers. If you need help deciding which model to select, please call our support team at 786.701.0700.
Here are a few quick references that may be helpful:
GRR X350 = 24V
GRR X400 v3 = 12V, Blue Housing Panels on Printer
GRR x400 v4 = 24V, Translucent Housing Panels on Printer