It vacuums the leaves up, cuts them into teeny-tiny pieces, and pushes them into a bag (which is really easy to empty into giant black leaf bags). It's shocking how much more compact the leaves are after they've gone through the vacuum.

https://www.lowes.com/pd/Toro-Ultra-Blower-Vacuum-Mulcher-260-MPH-340-CFM-12-Amp-Electric-Corded-Battery-and-Charger-NOT-Included/5014792053?gStoreCode=2293&gQT=1