New old stock Aprilia horn light switch.
Switch cover is stamped 'APRILIA' 'HORN' and 'LO-LIGHT' with 'APRILIA' on the horn button as well.
Switch base is molded with 'APRILIA' and '17267' in the plastic.
Switch handlebar mount is molded with 'APRILIA' and '17876' in the plastic.
Mount is for 7/8" handlebars.