Cartridge Part Number: SP Drum Unit 6400; Compatible Models: SP 6450, 6440, 6430, 6420, 6410; Number of Yield: Approximately 25,000 pages (When A4/5% printed); Model Number: 512684; Note: For RICOH SP Toner 6400 and 6400H Toner. Subsequent models are released. in the USA. Please make sure to check the compatible model before making your purchase.