HP - No. 21 Compatible Black Ink Cartridge (c9351a). Compatible HP Models: Deskjet: 3747, 3910, 3915, 3930, 3930v, 3940, 3940v, PSC: 1410, 1410v, 1410xi. MIPO (MP21) Black Ink Cartridge. ISO 9001 Certified. Compatible. 20ml Per Tank. Yield: Up to 200 pages.