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Substrate Materials Explained

Substrates are the rigid boards that we make our signs on.  The 4 different substrates offered at Fastpost are ACM (Aluminum Composite Material, Polystyrene, Corrugated Plastic, and Outdoor MDO.  Below explains what each material is and what application it is best suited for.


ACM (Aluminum Composite Material)

Our most popular substrate, ACM is made of two thin sheets of aluminum on both outer sides and a composite material in the middle.  The total thickness is approximately 3/16 inch.   ACM is an excellent choice for residential panel and riders. 



Another good option for residential panels and riders, Polystyrene is an economical solid plastic.  The Styrene we use is approximately 1/8 inch in thickness.  We have heard that Styrene can yellow over time, however we have not noticed this as we coat all our signs with a UV Laminate.


Corrugated Plastic

Our most inexpensive option of all substrates.  Comes in 4mil (approx. 1/8 inch) and 10mil (approx. 1/2 inch).  4mil is typically only used in residential environments.  4mil corrugated plastic is a good option for wire stakes and metal H frames.  10mil is great for commercial signs that will be attached to a building.


MDO (Medium Density Overlay)

MDO is an outdoor plywood made for sign manufacturing.  This is our "Go To" for all commercial signage.  We offer 1/2 inch thickness and comes in various sizes.  Sizes are 1x4, 1x6, 1x8, 3x4, 4x4, 4x6, and 4x8.