Roller system for manually winding up and unwinding a roller blind

The roller system has a roller blind (12), a winding roll (1) and two guide rails (7,7'), where a glider (10,10') is displaceably arranged on one of the guide rails. Two belts are provided, where each belt rotates two belt pulleys. The former belt pulley of the former belt is connected with the former belt pulley of the latter belt by a connecting shaft (4,4',5) in order to synchronize the movements of the two belts with each other. The glider is connected with one of the belts in each case. An independent claim is included for a roller unit for use in a roller system.