Orient Abrasives Ltd. Supplies Isostatically Pressed Monoblock Stopper - MBS. Orient Abrasives Ltd. Is an ISO 9001 certified company. Orient Abrasives Ltd. Manufactures calcined and fused alumina products. Isostatically Pressed Monoblock Stopper - MBS is used to control the flow of steel through the tundish nozzle. Isostatically Pressed Monoblock Stopper - MBS is made of magnesia carbon or alumina carbon quality with special compositions at the tip and slag zone to suit customer requirements. It is available with cross pin or screw fastening or gas purging facilities which are provided as and when required.