dense material

Translations
плотный материал
The jacket is made of dense material to keep him warm.
Куртка сделана из плотного материала, чтобы согреть его.
Definitions
A dense material is a substance that has a high mass per unit volume, meaning it is compact and heavy for its size. This property often results in greater strength and durability compared to less dense materials.
Words
dense

adjective
плотный
material

noun
материал