On the N50 towards Kampen, in a strong crosswind, you notice your roof-box load protrudes 25 cm to the side. Is that allowed on a car?

No — the side limit is 20 cm

Yes, as long as it is well secured

Yes — up to 10 cm is allowed at the side

Explanation

False — trap: securing counts. Lashing it down does not change the 20 cm limit (Book p.227-229).