This is a helmet holder for Aprilia RS 660 and Tuono 660, equipped with OEM rear seat and luggage rack. You will need 2 short screws to install this item and it can be installed on either the right or left side of the bike. It must be in the front tie hole, otherwise the back seat will be crooked. This holder is designed to fit a D-ring style helmet strap. Designed in Tinkercad.