A bolt 100 for a flywheel mounted blade where in the bolt comprises a head section 110; and a shank 150 extending from the head section, wherein said shank comprises a first section 120 comprising a circular cross section, a second section 130 comprising a geometric, oblong or oval cross section, and a third section 140 comprising a thread for a nut. The head section may be frustoconical in shape and have a planar face 111. The three sections on the shank may be adjacent to one another. The geometric shaped cross section may comprise of any known shape, and the edges may have chamfered or rounded corners. The bolt may comprise a first cross sectional diameter which is greater than or equal to the longest cross sectional dimension of the second section. The bolt may be part of a kit of parts comprising blade carrier having an aperture to engage with the second section of the bolt, a blade comprising an aperture to engage with the first section of said bolt, a bolt and a nut to engage the thread of the third se
