THIS ITEM IS A COMPLETE SET OF REPLACEMENT LINERS FOR THE BEARDSLEY AND PIPER MODEL 75B SAND MULLER, A TYPE OF HEAVY-DUTY FOUNDRY EQUIPMENT UTILIZED IN METAL CASTING PROCESSES FOR MIXING AND HANDLING FOUNDRY SAND. THE COMPLETE SET INCLUDES THREE SPECIFIC COMPONENTS IDENTIFIED BY THEIR ORIGINAL EQUIPMENT MANUFACTURER OEM PART NUMBERS. THE MIDDLE LINER IS OEM PART NUMBER 74804, THE END LINER CARRIES OEM PART NUMBER 74803, AND THE DOOR LINER IS SPECIFIED BY OEM PART NUMBER 78402. THE MODEL 75B MULLER SYSTEM IS KNOWN TO UTILIZE A NI-HARD MULLER BOTTOM AND CAN BE CONFIGURED FOR HEAVY DUTY OPERATION.