Seamless design, using the highest quality materials and lubricants, minimizes print head wear.Compatible Printers: OKI Microline 5520 eco, OKI Microline 5591 eco, OKI Microline 5590, OKI Microline 5590 eco, OKI Microline 5591, OKI Microline 5521 eco, Unisys UDS 1491, OKI Microline 5521, OKI ML 5500 Series, OKI Microline 5500 Series, OKI Microline 5520, OKI ML 5521, OKI ML 5591, OKI ML 5521 eco, OKI ML 5590, OKI ML 5591 eco, OKI ML 5520 eco, OKI ML 5590 eco, OKI ML 5520