With 1″ I.D. Clamp-on mount. ECE approved. Die-cast construction with an adjustable stainless steel ball socket construction, allowing left/right side or up/down installation. Clear convex tempered glass to widen your field of view for added safety. With universal CNC machined 6061-T6 billet aluminum P-clamp to clamp directly onto the handlebars. Head dimensions approx. 5 3/8″ (13.7cm) x 3 5/8″ (9.2cm).