a) Remove the screw with nut and washers (2 + 3 + 4) from the probe (1), then
place them in the lower end of the lower tube (5), insert this tip into the
mounting spots of the probe (1) so that all holes coincide in one line. Now insert
the mounting screw (4) through these holes and tighten at the other end with
the nut (3), but not too tight - see the picture below:
b) Press the latch on the other end of the lower tube (5) and connect it to the
middle tube (6) - the latch on one should click into the hole in the other: