Apparatuses, systems and methods are presented for handling calls. The core is formed with a slit extending completely through in the thickness direction from the upper surface to the lower surface and extending in the longitudinal direction from the front waist region to the crotch region. The housing attachment portion 12 is divided by a slit 14 formed in a central part thereof into both side arms 13, each of which has a hook 13a provided at the top thereof. The fast-flowing air flows quickly along the passage, so as to effectively cool down a working temperature of the specific electronic component, thereby increasing a lifetime of usage of the specific electronic component.