Pops on easily, no Velcro, fits most anyone * 3M scotchlite(tm) reflective material * Tangerine, yellow and white reflective up to 1500 feet and material is ANSI 107-2004 compliant * Pink, red, blue, and green reflective up to 500 feet * Large 1.25 inches by 14.75 inches; Medium 1.25 inches by 11.75 inches