Description: Easy to install and useful adapter These adapters will screw into your 10mm counterclockwise threaded mirror mounting point and then you will be able to mount the 10mm mirrors. (Note: The visible screw threads are counterclockwise, the thread that can not be seen are clockwise.) Thread Diameter: 10mm Screw thread: Right-handed (RH) thread / left hand (LH) thread Specification: Color: Black Size( W): 26 x 15.5 mm/1.02 x 0.61 inch Material: Steel Metal What is RH and LH screw thread and how do I know which one should I purchase? When a point of view on the axis through the center of , moves away from the viewer when it is turned in a clockwise direction, and moves towards the viewer when it is turned counterclockwise. This is known as a right-handed (RH) thread, because it follows the right hand grip rule. Threads oriented in the opposite direction are known as left hand (LH). In : Right-handed (RH) thread: Tighten the screws in a clockwise direction. left hand (LH) thread: Tighten the screws in a counterclockwise direction. Fitment: Fits Most Motorcycle, Street Bike, Cruiser & Chopper Models. Package Includes: 2 Pieces Motorcycle Rearview Mirror Adapter Bolts(6 Pack) Note: 1.Please allow 0.1-0.3cm differences due to manual measurement, thanks. 2.Please understand because of the light irradiation or computer display difference, so I can not guarantee photos and real color is the same.