Sieve sleeve, ETA-approved for the use of injection mortars in perforated or hollow stone, suitable for M10 and M12 threaded ends. You drill with a diameter of 15 into the hollow stone, inject two thirds of the sieve sleeve with injection mortar, place the sieve sleeve in the drill hole and insert the threaded rod with a rotating movement within the prescribed gel time. Mortar will be forced out through the meshes of the sieve sleeve, creating a plug in the hollow chambers of the stone that hardens there