Need that little detail to make your rocket one of a kind? Like to have every little detail just right? Well, here’s what you need: screws and bolts! Screw heads are silver with black phillips center. Hex head bolts are all black. They come in 4 sizes: 3/16″, 1/4″, 3/8″ and 1/2″ with 100 screws or 150 bolts per sheet.