Described herein are embodiments of systems and apparatuses that include a dart and/or a clutch for a dart plunger. In an exemplary embodiment, the clutch consists of a one-piece unit having a length, an outside diameter, and an inside diameter where at least a portion of the inside diameter is sized to create a frictional interface with a dart. The clutch may also include a gap, a slot, and/or a spiral cut. The dart may include a shaft having opposite ends and a shaft diameter that varies between the opposite ends.