The document discusses various types of GRP (Glass Reinforced Plastic) cable trays used in electrical infrastructure, highlighting their advantages over traditional materials like metal and plastic. It describes different tray designs, such as solid bottom, ventilated, ladder, wire mesh, trough, and single rail, each suited for specific environments and cable types while addressing their benefits and limitations. GRP cable trays provide a durable and efficient solution for cable management, particularly in harsh conditions.