One mesh with 4 different materials , every material has own maps.
Using 2K textures.
Types of barrels:
Type 1 :
Is a simple barrel , no logo , just metallic with rust and dirt.
Type 2:
Is a biohazard barrel , yellow , some rust , dirt and biohazard's logo.
Type 3:
Is a fuel barrel , red , some rust and dirt and NO-FIRE logo.
Type 4:
Is a OIL barrel , black , with some rust and dirt and OIL Logo (hand-made).
You can use them for your game like : FPS , Zombie ... anything , there are a lot of details on them.