All bones, but somehow it bleeds! Our Bleeding Skull Mask is made of molded plastic and features a sinister grinning skull face. This Skull Mask bleeds by means of a hand-held pump that you control, forcing the fake blood out and over the mask to be collected at the bottom and recycled at your pleasure! Bleeding Skull Mask is held in place by an elastic band that fits around the back of the head. One size fits most teens and adults.