hard steel plug

steel (cold steel)

hard fiber plug

water jacket plug / water-jacket plug

appliqué steel armor

caterpillar steel track

cold steel/ weapon

electro-slag refined (ESR) steel

high-strength steel

homogeneous steel casting

single-strand, high-strength, spring-steel wire

steel bar

steel core

steel helmet

steel obstacle

steel shaft

steel spheres

all-welded cast steel turret

anticorrosive barrel steel

armor steel door

armor steel fuel tank

carbon gun steel

gun steel alloys

steel-tube framework

welded steel-tube framework

silicon-manganese steel

neutron-resisting boron-composite steel armor

hard

hard base

hard core

hard intelligence

hard kill

hard power