http://www.airsoftretreat.com/gallery/data/624/medium/8.jpg
This picture contains both the air nozzle and tappet plate.
==== ICS Note: ====
The tappet plate in ICS mechboxes has been reported to be very brittle when compared to TM and Guarder tappet plates. It has a rather well-documented history of snapping in various places for no apparent reason. It may be a good idea to pick up an aftermarket tappet plate if your gun hasn't had this problem.
=== IIe. The Piston: ===