We carry a complete line of Lau Fan Blades & Blower Wheels. It is important to measure the width to center of the blade times two. The next step is to determine the pitch or angle of the blade and then the bore size. This is the size of the shaft.. usually 1/2" or 5/8" on prop blades and 3/4".5/8" or 1" on Blower Wheels 2-Blade Propellor 3-Blade Propellor 4-Blade Propellor 5-Blade Propellor Blower Wheels Slinger Fan Blades Fan Blade accessories Let us help you through the selection process. Value ac is a proud distributor of Hart and cooley registers, air diffusers, vent covers, and air conditioning vents. We can special order anything you need. Please call us at 1-888-242-7725 Toll Free for a quote. We want to earn your trust! Floor Registers and Vent Covers Blog