Our patented Quick Clip™ technology has built-in spring loaded clips that hold lights securely in place. Each light is adjustable and rotates, and the clips can easily be removed. You don't need to separately purchase any tools to hang up these lights. The 24 LED Energy Star-rated bulbs are environmentally friendly, remain cool to the touch, and reduce power usage. Each 16' strand has plug-ins at both ends, allowing you to link up to 90 strands.