Spacesaver Corp., a Fort Atkinson manufacturer of high density mobile storage and filing systems, recently completed a $7.5 million, 45,000 square foot expansion. The expansion resulted in 20 new jobs, the company said. Spacesaver has 508 employees. Spacesaver, a division of Green Bay-based KI, began the expansion last fall to accommodate production of its XTend Mobile High-Bay Storage (MHBS). The system is designed for academic libraries, government and commercial entities that require efficient off-site media storage.