COREBOX -- ADDING A SATA SSD INSIDE THE BOX?

WHEN I OPENED THE COREBOX, I INSTALLED THE ENCLOSED NEW SATA PLUG AND PUT IN A 480 GB SSD. MY QUESTION IS IT IS PRETTY BIG–I SUSPECT 2.5 INCH OR 5 INCH SSD AND I PUT IT IN THE BOX WITHOUT SCREWS. MY CONCERN IS THE HEAT DISSAPATION. I DID NOT INSTALL WITH SCREWS BECAUSE I COULD NOT FIND WHERE TO INSTALL THIS SSD; SO I PUT IT IN THE BOX WITHOUT SCREWS. IT IS AN INTERNAL SSD. IS THIS OK FOR HEATING PURPOSES?