ABSTRACT OF SUPPLEMENT Our Nathan Shock Center (NSC) of Excellence (P30 AG068345) provides access to geroscience technology, research training, and research support for geroscientists across the United States. NSCs focus on the basic biology of aging and thus use a variety of methodologies and technologies to advance our understanding of geroscience. Users of our NSC study a variety of biological variables at the molecular, cell, tissue, organ, and organismal levels. In addition to the requests from the geroscience community to use the vast resources of our Geroscience Technology Core (GTC) and the expertise of our NSC faculty at USC, we are often asked if we can couple these powerful studies with measurements of mitochondrial function and cellular metabolism. Currently, our Seahorse instrument (>10 years old) does not provide adequate sensitive for the cells, tissues, organoid samples of our awardees and potential applicants. As such, this lack of opportunity represents an unmet need of the community of geroscience researchers that utilize our NSC cores. In order to advance tour capacity to serve the geroscience researchers and projects performed at our USC mitochondria and metabolism core (>90% junior investigators and >50% from outside of USC), we propose the purchase of a new, state-of-the-art Seahorse XF Pro Complete. This instrument measures OCR and PER in a 96-well format, includes Wave Pro SW with Discovery License, ATP and 12 cartridges, XF Imaging and Cell Counting SW w/ hand wand and boasts a 35% increase in sensitivity, a 35% decrease in error range, improved design to minimize edge effects leading to a 60% increase in the number of usable wells, and provides access to new kits and reagents designed specifically for the XF Pro that our junior faculty and trainee awardees have requested. These measures are essential to our ability to fully understand the underlying basis of aging and age-related diseases across all hierarchical levels. Our administrative supplement will establish a powerful new tool in the arsenal of technologies in the Geroscience Technology Core (GTC) at USC. These new technologies represent an unexpected opportunity for USC to advance the research services, available to all geroscience users of our NSC services at the Leonard Davis School of Gerontology at USC (always prioritizing junior faculty and emerging geroscience researchers. As such, our administrative supplement will greatly impact geroscience nation-wide.