bulb tee
High-strength, lightweight, steel sections used as sub-purlins in specialty roof decks such as structural cement fiber tile, precast or poured gypsum, and poured light weight concrete. Bulb tees are superior to cold-rolled, or built-up subpurlins of light gauge sheet metal, in part because bulb tees are hot rolled from high-strength rail steel for high tensile strength and design stress.