Hardwoods without defects and joined using phenolic glue to make it waterproof. The name "marine" is derived from the fact that these type of boards are made for marine use and in wet or humid conditions where normal plywood cannot be used.
Marine boards are more durable, waterproof and stronger so they can hold more weight than normal boards. Due to these properties they are used mostly in yachts, trucks, ships, outdoor buildings, outdoor storage, boats and docks among other structures that need to weather the elements.
because they have more layers joined together. It is also due to the fact that they are joined together using high-quality waterproof glue which adds to the strength of the boards.
To ensure the board can carry more weight, the wood used has negligible core gap which ensures the glue bond with the wood is strong.