proof-of-concept aircraft

immersion-proof

pierce a bullet-proof vest

water-proof cloth

armor ballistic bullet proof face mask

fume-proof

bomb proof shelter / bombproof shelter

bomb-proof

bomb-proof protective deck

corrosion-proof

wearing-proof alloy

explosion-proof tank

incremental proof testing

freeze-proof

fuel-proof

gun proof mark

musket-proof

sound-proof compartment

corrosion proof

rust-proof

heat-resistant vibration-proof pressure indicator

A-proof

jamming-proof modules

sabotage-proof

pattern of proof shooting

proof shot

radar-proof

cannon proof

cannon proof armor

blast-proof container

radiation-proof

commander’s concept

commander’s intent and concept