Specifications Technology, Speed and Print Characteristics • Printhead: SIDM – ML420/421 9-pin; ML490/491 24-Pin • Graphics Resolution: ML420/421 – 240 (H) x 216 (V) dpi maximum; ML490/491 – 360 (H) x 360 (V) dpi maximum • Feed Rate: 4.5 ips (11.4 cm/sec.) • Print Speed (cps): LQ NLQ Utility HS Draft SS Draft ML420/421 n/a 95 380 510 570 Pitch (cpi) 10 10 10 12 ML490/491 105 n/a 315 420 n/a Pitch (cpi) 10 10 10 Emulation, Interface and Memory • Emulation: ML420/421 – Epson® FX, IBM® ProPrinter®, OKI MICROLINE ML490/491 – Epson LQ, IBM ProPrinter, IBM AGM, IBM XL24 • Interface: IEEE Parallel and USB on all models; also available with RS-232C Serial or OkiLAN® 10/100 Base-T Internal Print Server standard (see Ordering Information); Options include RS-232C Serial and OkiLAN 10/100 Base-T Internal or External Print Servers • Memory: 128K Compatibility • Operating Systems: Windows® 7, Vista® 32/64, XP, 2000, LINUX Paper Handling • Paper Input: Single-part, Multi-part, Continuous forms, Cut sheet, Index stock, Envelopes, Labels • Number of Copies: ML420/421 – original + 5; ML490/491 – original + 4 • Thickness: 0.017" (0.43 mm) maximum • Paper Feeding: Rear Push and Friction Feed • Options: Bottom Push Tractor, Top Pull Tractor, Cut Sheet Feeder, Roll Paper Stand