The Hindsight LS (Lane Split) Bar End Mirror was created by adding the folding / retractable feature to the original Hindsight. There are two primary benefits of the retracting bar end mirror-added clearance during tight riding conditions, and reduced width for bike storage. Simply pull in the bezel of the mirror to create additional clearance, then fold the bezel back out against its positive stop in the full open position and the sighting of the mirror returns perfectly to its rear vision position. The detent folding mechanism is calibrated to retract should the mirror contact an immovable object, thus allowing forward motion without disruption of steering control. The pivot of the hinge features a ball / spring detent which holds the mirror bezel in the full open or full retracted positions. The pivot also features dust rings that provide for years of maintenance free operation. These mirrors are somewhat universal since they simply clamp on to the handlebar. So if you're installing them on an older airhead (1970-1995) all you will need to do is move your controls in 10mm. If you have a newer BMW then its requires a little more. You will have to re-drill holes for the set screws that hold on the control unit. If you're installing a new handle bar then that would be an ideal time to upgrade your mirrors! Sold individually, left and right side.