 Under fire, the forts were damaged by 21 cm fire and could not withstand heavier artillery.The large weapons were all German products, made by Krupp in Essen, but the armor was by Cockerill (Belgium), Ateliers de Creusot (France) or Grüson (Germany).The fort was provided with signal lights to permit communication with the neighboring Fort de Lantin and Fort de Hollogne.