Abstract: Pivotable side cores for a lower mold part in a concrete casting machine of the kind typically used for making cast items in the form of concrete blocks for pavements, wall construction or elements, solid blocks and blocks with cavities or recesses. By the pivotable side cores, recesses can be made at the side of products, where these recesses at the side of the product do not extend through to the top side of the product. By the invention are indicated pivotable side cores in a lower mold part including means that ensure that the core members forming the cavities retain their position in the lower part during compression, and at the same time are pivoted off the product during the demolding.