Aerospeed BX100 High Performance Box Fan with Handle, 5-Blades, 3-Speeds, 20" Winter_Items Knurled knobs let you adjust

Knurled knobs let you adjust the orifice plate without wrenches

Converts easily from a sander to a polisher

Anodized aircraft quality aluminum

Center Screw Thread: 5/8"-11

Aerospeed BX100 High Performance Box Fan with Handle, 5-Blades, 3-Speeds, 20" Winter_Items Knurled knobs let you adjustThe Camair Aerospeed 20" Box Fan is an energy efficient and cost effective way to keep cool. With 3 speeds, a permanently lubricated motor, and a 5 wing propeller, this model does the job every time. The top mounted speed control dial provides easy access while the convenient carry handle make this unit ultra portable; so, you can take the cool with you. Top mount Sleek wave grille design Energy efficient Ergonomic carrying handle Heavy duty steel