Yes, you can have several colliders of same type in the same object

[Marzoa]

Hi there,

There is a bunch of people there that keep saying that you cannot assign more than one collider of the same type to an object, but this seems to be false, indeed. I am actually doing it, and it is working perfectly. So, what’s the matter with this? Is there any official recommendation to avoid this, despite the editor lets you do it? Or it is just kind of an viral urban legend?

[fffMalzbier]

As official as is may get → A quote form the documentation:

Any number of these can be added to a single object to create compound colliders. With careful positioning and sizing, compound colliders can often approximate the shape of an object quite well while keeping a low processor overhead. Further flexibility can be gained by having additional colliders on child objects (eg, boxes can be rotated relative to the local axes of the parent object). However, you should be sure that there is only one Rigidbody and this should be placed on the root object in the hierarchy.

Unity - Manual: Introduction to collision

[Marzoa]

From your quote:

However, you should be sure that there is only one Rigidbody and this should be placed on the root object in the hierarchy.

A Rigidbody is not a Collider. But the quote is interesting, though. Maybe the whole confusion came from there.