advocate aegis arch dam arm guard back bamboo curtain bank bar barrage barrier bear-trap dam beaver dam boom breakwater breastwork brick wall buffer bulkhead bulwark bumper champion cofferdam contraceptive copyright crash helmet cushion dam dashboard defense dike ditch dodger earthwork embankment face mask fence fender finger guard foot guard fuse gate goggles governor gravity dam groin guard guardrail hand guard handrail hard hat helmet hydraulic-fill dam insulation interlock iron curtain jam jetty knee guard knuckle guard laminated glass leaping weir levee life preserver lifeline lightning conductor lightning rod logjam mask milldam moat mole mound mudguard nose guard pad padding palladium parapet patent pilot portcullis preventive prophylactic protective clothing protective umbrella rampart roadblock rock-fill dam safeguard safety safety glass safety plug safety rail safety shoes safety switch safety valve screen seat belt seawall shield shin guard shutter dam side with stone wall sun helmet umbrella uphold wall weir wicket dam windscreen windshield work