Lui/Luna/Vega/Cometa control grub screw
Finally the grub screw everyone has been waiting for. Made from pure unobtanium. Lambretta Concessionaires USA is proud to present the Luna Line Grub screw for the handle bars. Each Luna needs 2 of these. One on each handlebar. These Grub screws prevent the controls from sliding off the handlebars.
In the Luna Line parts manual, this is item 37 on page 39/40