The present invention discloses a transmit-receive front end. The endoscope includes a heater and a temperature sensor. The hub portion includes a lateral hub extension extending toward a distal end of the needle cannula, and the shield portion includes a lateral shield extension extending toward a proximal end of said needle cannula. The shoes have replaceable wear-strips. They can be used to produce coating colors, especially for inkjet papers or inkjet foils or other inkjet materials.