sentences:  Radial tipped – These fans have wheels that are backward curved, but in a way slightly different from backward curved fans.Backward curved fans have wheels whose blades curve outward, while radial-tip fans' blades are curved inward and radial at their tips (hence the name "radial tip"), while still in a backwardly-curved configuration.Their curvature can also be thought of as radial at the tips but gradually sloping toward the direction of rotation.