U fittings are used to make lintels over window and door openings. They form a heat-insulating layer, while eliminating additional formwork. U-shaped pieces should be built on a previously prepared base, stamped from below. After bricklaying, install the reinforcement resulting from the documentation and pour concrete. In the case of openings in the window and door appearing in the outer walls of the building, U-shaped elements should be insulated. 20 PLN is added to the price - the cost of the pallet.