Cove Concrete Linear Gas Fire Pit - 48", Natural Grey, Electronic Ignition (Natural Gas). The Cove Linear Concrete Gas Fire Pit is the statement piece that transforms your backyard project from ordinary to extraordinary. Crafted from premium Supercast™ concrete which is a GFRC fire pit with a sleek, contemporary profile, this fire pit brings modern sophistication to any landscape design. Special order - contact us for a quote.