This glow in the dark dinosaur slumber bag is perfect for all dino lovers. The dinosaur skeleton throw blanket sleeping bag is 66 inches long by 30 inches wide and features four common dinosaurs including, Triceratops, T-Rex, Brachiosaurus, and Stegosaurus. The nap mat is made from 100% soft, plush, polyester with polyester filling and is blue with white dinosaur fossils that glow green at night. Simply place the slumber mat in the sun or near a light for a few minutes and then turn out the lights to see the magical dinosaurs glow. After an hour of direct light this dinosaur blanket for boys and girls will glow for about a half hour or longer. Some light sources allow the dinosaurs to glow brighter than others. Below is a list of best to worst sources of light Direct Sunlight – BEST Black tube light Black / UV LEDs Fluorescent tube light Compact Fluorescent / CFL screw-in light Incandescent / standard light bulb Blue/purple LEDs White LEDs – WORST All dinosaur lovers are sure to enjoy this fun sleeping bag that magically glows. Not only is it soft and cozy, but it also works great at being a security sleeping bag for little ones and scaring those bad dreams or monsters away at night with its glowing dinosaur feature.