... solid mecury,high efficiency,friendly environmental,long lifetime t5 fluorescent Power: HE series:4w,6w,8w,13w,14w,21w,28w,35w ... >99%),low THD(<10%)4.Use tri-phosphor powder fluorescent lamp,more brightness,high efficiency5.No noise,no flicker ... up to 45%7.Installation:Ceiling mounting, series connectionApplication: House lighting, shopping mall,refrigeratory,show case,hotel,office etc t5 fluorescent