A: PCB material called FR-4, or Flame Retardant 4, is a commonly used epoxy resin fiberglass laminate. It is made of a thin layer of epoxy resin and a woven fiberglass reinforcement material. The epoxy resin provides good electrical insulation properties, while the fiberglass reinforcement provides strength and stability to the laminate. FR-4 PCB material is used in various applications, including printed circuit boards, electrical insulation, and structural components in electronics.

FR-4 is available in various thicknesses, with the most common being 0.8mm (.032″), 1.0mm (.040″), 1.6mm (.062″), and 2.0mm (.079″). These thicknesses are suitable for different applications based on mechanical strength and electrical properties.