A straight middle LED module having a certain length and positioned at a middle portion; side LED modules which are provided at both sides of the middle LED module at a regular interval along a longitudinal direction; a middle connection portion at which the side LED modules and the middle LED module are connected and integrally formed in order for the side LED modules to be bent; and a horizontal connection portion to which a lower side of the middle LED module is connected at a regular interval along a horizontal direction, and the middle connection portion has grooves alternately formed at both sides and has a width narrower than the width of the side LED module.