Crate

A crate is a common block in Junk Jack. When broken, a variety of items can come out, such as Nails, Widgets, Wood Planks, and more.

These come in different varieties - the more "armored" versions having better / more loot.
Health Crates have bandages and/or pills to heal yourself, these are less common. It is highly recomended that crates are broken on your first day