Symmetrical New Jersey barrier for use as protection in construction sites or enclosures, prefabricated from vibrated, reinforced concrete of the following class: Rck (resistance to compression) ≥35 Mpa, manufactured with cement type 42.5R and aggregates of quarry or of river assessed and washed, with dimensions of 62x620xh=... width in front of 13.6 cm, reinforced with caged B450/C steel, with a bar cover not less than 20 mm. The lower connection is held in place with a kit composed by a double-layer 280x80x10 mm plate with tie-rods, M24 nuts, and washers, all hot-dip galvanized. Manufactured by a company which has the certification of quality, UNI EN ISO 9001, certified by ICMQ.