2pcs OPC Drum Unit Compatible with iR2520, iR2525, iR2530, iR2535, iR2545, iR ADVANCE 4051, 4225, 4235, 4245, 4251, 4025, 4035, 4045.This cylinder unit is designed for use in laser printers and copiers as a replacement component for the imaging drum.Each set includes two drum units to support continued and maintenance of compatible devices.The drum is engineered to work within specified printer models to facilitate consistent image transfer during printing processes.