Marvin A. Salzenstein, age 91, retired respected mechanical engineer and Founder of Polytechnic, Inc.; loving father Alan Salzenstein and the late Lauren (late David Gordon) Salzenstein Gordon; adored grandpa of Ethan and Gabe Gordon; treasured cousin of Elaine Schultz and Aline Neimetz and their families. Marvin was lovingly cared for by Vinnette Donalds. The graveside service and shiva will be private. The livestream will be Monday, 10:00 a.m. CST at www.goldmanfuneralgroup.com. Under Recent Services, click on Marvin’s photo and scroll down to Service Details to view the service. The livestream will be up 15 minutes prior to service. Contributions may be made to Keshet Gadol, www.keshet.org. Info: The Goldman Funeral Group (847) 478-1600.