It’s crude looking with rough edges and dents in the surface giving it that classic homemade bomb look.
Turning it over he flips one of two switches on the back and a green LED lights up next to a dial which he leaves untouched. The underside has a round flat surface which he holds against the metal leg of the workbench and then remains in place as he lets it go. A magnetic mine with a timer. Much more convenient than the claymores he had to drive into the ground. The concrete surface that covered most of the town made it difficult to position them correctly. This gave him options, better angles - more colours on his palette to paint with.
He removes it and turns towards the weapons racks. Standing about two meters from it he gentle tosses the mine