Oki ML 520 Oki ML 520 Elite Oki ML 520 Series Oki ML 520 n Oki ML 521 Oki ML 521 Elite Oki ML 521 n Oki Microline 520 Oki Microline 520 Elite Oki Microline 520 Series Oki Microline 520 n Oki Microline 521 Oki Microline 521 Elite Oki Microline 521 n