Dimensional letter signs are logos or lettering typically made from Compoiste materials, aluminum, PVC or acrylic with a three-dimensional appearance. This lettering is normally lit from external lights either above or below the sign. Aside from aluminum and acrylic, you can choose from materials such as plastic, foam, steel, and wood. These signs are often layered on backer signs and allow for a rich look that has true shadow lines, increasing the appeal of the sign.