DESIGNED SPECIAL FOR STRIP LIGHT. 11.15mm hollow distance, 2mm hollow height, it can be screw(not included) tightening, and self-adhesive, or use together. Three installation methods could be selected. Coping with various surfaces, ideal for 3528/5050/5630/3014 SMD LED strip light within 10mm wide. Recommend to use 2-3pcs for 1-meter strip lights