The latch was in use for calling the neighbors, by means of a certain cadence of blows. That of the house Calvet is of wrought iron and the blacksmith was Joan Oñós. It is notable for the beautiful design, for the difficulty of execution and for the symbolism of the ornamental motives. The latch is a Greek cross, that is to say with four equal arms. On having gesticulated it and to strike the door, it squashes to a bedbug. The whole set is on four bars of Catalonia's shield. The bedbug, "cimex lectularius", is an insect parasite that absorbs the blood of the persons and transmits diseases. It represents to the sin and probably in a special way the blasphemy, for which Gaudí was feeling a great distaste. The cross of Jesus Christ squashes to the sin; it is a symbol of the redemption and, more especially, of the sacrament of the confession.