Xml for x 55

So whats the action called for the z axis because i cant seem to put anything on that. this is how i have it now:

	<action name="v_pitch">
		<rebind device="joystick" input="js1_y" />
	</action>
	<action name="v_yaw">
		<rebind device="joystick" input="js1_x" />
	</action>
	<action name="v_roll">
		<rebind device="joystick" input="js1_z" />