insulation

hi,
anyone used some foam like the one used for mattress for insulation in their teardrop?
I have access to a large quanties of foam like the picture above in 3 different thickness for free . I will use some to re-do my mattress but i was wondering if i could use it as insulation?
anyone used some foam like the one used for mattress for insulation in their teardrop?

I have access to a large quanties of foam like the picture above in 3 different thickness for free . I will use some to re-do my mattress but i was wondering if i could use it as insulation?