Thickness of FRP side rail for LH Series is 6mm unless otherwise specified. FRP cable tray is the support system for managing cables and protect cables from heating, rains and corrosive elements. They are widely used in chemical plants, building con-structions and residential life by virtue of its. four-bolt pattern for 3, 4, 6 and 8" tray depths Cable tray made of fibreglass (FRP/GRP). Suitable for electrical and instrumentation installations. Cable tray made of fibreglass. SCOPE OF WORK: Scope of work includes 1. We cover specifications, standards compliance, and application guidance for engineers. Cable management infrastructure is a critical but often underspecified element of industrial and commercial electrical.