housing 35 and is connected to one of the belt retractors not shown the belt retractors in housing 35 may be chosen for example from those disclosed in the following u s pat nos 4 056 242 4 580 812 4 655 312 4 667 904 4 669 680 4 700 974 4 726 537 4 747 565 4 787 569 4 830 310 and 4 907 757 pulleys 33 and 34 are automatically moved along track or tracks 20 using any suitable means not shown although track or tracks 20 preferably comprises a groove in which pulleys 33 and 34 are disposed pulleys 33 and 34 move belts 31 and 32 respectively from the inoperative position see the position of belts 131 and 132 in fig1 in which belts 31 and 32 do not interfere with movement of the user to the operative position see the position of belts 31 and 32 in fig1 in which belts 31 and 32 restrict movement of the user automatically when for example seat 15 is sat upon or the ignition key of car 14 is turned or door 17 of car 14 is closed when system 11 is moving from the inoperative to the operative positions seat belt pulley 33 and shoulder belt pulley 34 move along track or tracks 20 from the first end 23 of ceiling portion 21 along ceiling portion 21 forward of the torso.