What is the difference between a retractor and a manual belt?

Q’STRAINT automatic and semi-automatic retractors dramatically decrease the time it takes to secure a wheelchair and eliminate the guess work of proper passenger securement. While manual belts can still be effective, retractors boast many additional features that manual belt systems cannot match.

Compare systems:
QRT-360 Retractor
QRT-1 Series Retractors
M-Series Manual Belt