The primary objective of this project is to provide maintenance and repair services for an existing Leica Stellaris5 STED super–resolution microscope located in the CCR Microscopy Core of the NIH/NCI/CCR/LCBG used for fixed and live cell confocal and super–resolution imaging of cancer cells and tissues in 3D to further cancer research. The Contractor shall provide all labor, materials and equipment necessary to maintain and repair one (1) Leica Stellaris5 STED super–resolution microscope located in the CCR Microscopy Core in building 37, Room B114. This microscope is used by NCI researchers for live cell and super–resolution imaging of cancer cell lines and organoids. All repair services shall be performed on–site in accordance with the manufacturer`s standard commercial maintenance practices, unless the vendors best judgement requires the instrument to be depot serviced.