[Solved] Role: downloadable

[ClaudioRomeo]

Please, pardon the stupid question (and my bad English).
But when I create a media file (like a .mp4 video or a .pdf document) and assign the role: downloadable to it, I anyway need a plugin to make it really downloadable (for free)?
If not, there is something that goes wrong: such media file acts as displayable if image or pdf, and if video or audio it isn't shown at all in front end.
I searched the forum and googled for it, but everyone says "mark it as downloadable" and no more...

J 3.6.4
VM 3.0.18
php     5.6.23

[GJC Web Design]

I have used this one (yes.. u need a plugin afaik)

https://www.spiralscripts.co.uk/joomla-plugins/spiral-free-download-plugin-for-virtuemart-detail

[ClaudioRomeo]

Now it's clear, GJC Web Design.
Thank you.