Laser Tek Services &reg; Drum for Brother DR-520 TN-550 TN-580 Do-It -Yourself-Kit!! For use with the Brother DR-520 Drum. Drum lasts 20,000 pages at 5% coverage. Drum unit installs easily. Free email & Toll FREE phone support. Kit comes with an instructional material for easy drum remanufacturing. Save big each time you use compatibles and GO GREEN!!!