This propeller is made of high quality carbon fiber， which is extremely lightweight and durable and It is just designed for RC electric 500 helicopter . You can expect an increase in overall motor efficiency with this excellent propeller.<br> <br> Description:<br> Carbon fiber 430mm main blades<br> Material: Carbon fiber<br> High Thrust<br> High durable<br> Extremely lightweight<br> Suit for RC electric 500 helicopter<br> <br> <br> Parameter:<br> Length: 17 Inch/430mm<br> Material: Carbon Fiber<br> Shaft Hole diameter: 3mm<br> Propeller thickness (close to shaft hole): 10mm<br> Product weight: 119g<br> <br> Package information:<br> Package size: 43 * 4 * 1 cm / 17 * 1.6 * 0.4 in<br> Package weight: 123.5g / 4.3 oz<br> <br> Package list:<br> 1 * pair Carbon fiber 430mm main blades<br>  <br>  <br>  <br>  <br>  <br>  <br>