Through the clever and ultra-thin design of adjustable lamps, and the minimum height of lamps is controlled in the range of 75 mm. In satisfying the inside height 80 mm under ceiling, it maximally saves the indoor space. And in view of the small size light's new spring design, under the condition of meet the polarization of 30 degrees, it can effectively solve the problem of installation requirements on thickness 8 ~ 20 mm of ceiling. Design innovation and practicality is presented incisively and vividly in the research and development and application of the LINNOU series downlight.