+3 F500 00008 €490 In stock Quantity: 1 Add to Bag Product Details UIM class F500 racing propeller. Fits 12:15 or 13:14 gear ratio with shaft diameter 15mm and shearpin 5mm. About size(pitch and diameter) and cupping: Pitch determines the max speed that this propeller can achieve. Diameter varies blade area, therefore affects grip. Bigger diameter = more grip. Cupping varies from 1-6, where 1 is very "slippery" and 6 has very good grip. The recommended sizes are preselected for your convenience. If the propeller is to be used for UIM racing then preselected variant can be good average choice. Save this product for later Favorite