The new GL ACER stainless steel evaporative cooler for rooftop mounting comes with an energy-efficient motor, direct-drive tubeaxial fan, corrosion-proof air blades, stainless motor mount, 18-ga stainless steel casing sump, premium-efficiency stainless steel pump, and heavy-duty brass water fill valve, says the company. The unit uses half the energy of conventional coolers and produces 20% more cooling, the manufacturer says.