First Trip Around The Sun Yard Sign Cutouts, First Birthday Party Theme Decorations Props, Space Theme Birthday Yard Signs With Metal Stakes. Economical and durable, our Coroplast Yard Signs are a staple of outdoor advertising. These First Trip Around The Sun Yard Cutouts Outdoor full color direct printed graphics are vertically fluted for use with a Stakes. Coroplast is typically used for yard, parking, real estate, and election signs. They are waterproof.