Well-designed built-in spring telescopic and rotation combo system, perfect for soft tip and steel tip darts. Rotation(without wobbling) any allows each dart to be more closer together, avoids flights ripped out caused by hitting previous dart, telescopic prevent dart's deflection when hit the previous dart, both assure the flights more durable use.
Octagon shape on edge of the shaft screw helps to tighten and loosen the shaft more easily. Extra twin strengthen line molded at the end of the screw, holds the shaft incredibly tight to the barrel- even when shooting.