Ducati MONSTER 620 Manuel D'utilisation Et Entretien page 125

Change th bulbs (4).
Note
Be careful to hold the new bulb at the base only.
Never touch the transparent body with your fingers or it
will blacken resulting in reduced bulb brilliancy.
Insert the locating pegs of the bulb base into their seats to
obtain correct alignment.
Engage clip end (3, fig. 46) into the headlight body mounts.
Reconnect the cables.
Disconnect the connector to change the parking light bulb.
The bulb (5) has a bayonet base: press and twist counter
clockwise to remove. Fit the spare bulb by pressing and
turning clockwise until it clicks. Refit the connector and
secure the rim/reflector unit.
4
5
E
fig. 47
fig. 48
51