Abstract: An arrow nock having a telescoping impeller and housing with resilient means for enhancing the acceleration of launch. In various embodiments, effective together or independently, the housing and impeller are configured and coupled to: create arrow rotation during launch; grip the bowstring during notching and release it during launch; and generate tracking signals.

Abstract: An embodiment in accordance with the present invention provides a blower and a method for landscaping and lawn maintenance. The blower includes an outer housing having an inner chamber, the outer housing defining at least one discharge port and an impeller disposed within the inner chamber of the housing. The impeller has a first side surface and a second side surface, wherein a first plurality of blades are mounted to the first side surface and a second plurality of blades are mounted to the second side surface. The second plurality of blades are a mirror image of the first plurality of blades. Air or other fluid is expelled through the discharge ports and can be directed using discharge tubes in order to redistribute debris or fluid.