Halloween Glow-In-The-Dark Green Spider Decoration. These green spiders are a fun addition to Halloween parties, haunted houses or just around the house.  Place these creepy crawly spiders on a shelf all by themselves or tuck them inconspicuously among other Halloween decorations, where guests will least expected them!  Plastic spiders are a 2 - ct packs of 4" x 6" green spiders.  Halloween Party Favors Glow In Dark Spiders.