Assertion: ball's design | /r/HasProperty | hollow section of steel pipe
Facets:
Source sentences:
text: There are dozens of variations of the shrapnel bomb, but most follow the basic design of a pipe bomb: a hollow section of steel pipe capped at both ends; a low-grade explosive element (either gunpowder or some chemical compound) attached to a fuse; and metal shrapnel packed inside the hollow pipe.