1. The fan blade has diameter - 36" or diameter - 42" 2. Five blades for 36" fan and 6 blades for 42" fan. 3. Blade, shell, shroud, and screen of rotation are hot-dip galvanized of rusty-resistance. 4. Can be installed a thermostat to control the temperature which is option. 5. Motor: 1/2hp, 2.8amps, 50Hz, 577 blade r.p.m. or motor: 1/2hp, 3.0amps, 60Hz, 591 blaee r.p.m. 6. 120 degree coverage, 15 ~ 20m.