Shingle material is a type of roofing material that is used to cover the exterior of a building. The two most common types of shingle materials are SLATE and CEDAR, both of which have five letters. SLATE is a type of metamorphic rock that is formed from sedimentary rock due to extreme heat and pressure. It is known for its durability and is often used in roofing applications. CEDAR is a type of wood that is known for its resistance to rot and decay, making it an ideal choice for outdoor applications. Both SLATE and CEDAR are popular choices for shingle material due to their durability and resistance to the elements.