Abstract: The invention relates to a guide unit (1a) associated with a traction drive means, which guide unit (1a) comprises a tensioning element (3a) and a guide element (4a). The components: the tensioning element (3a) and guide element (4a), which are displaceable separately from one another with respect to a housing (2), are associated with separate regions of the traction means (8) in the operating state of the traction means drive.

Abstract: A hydraulic tensioner for traction means, especially of internal combustion engines is provided, and includes a tensioner piston, in the bottom of which an externally opening pressure relief valve is disposed in an axial central bore. The central bore is provided with a hole and is secured with a pot-shaped cap which rests against the piston bottom and is frictionally engaged therewith. In order to make the hydraulic tensioner inexpensive to produce and easy to handle, the pot-shaped cap is provided as a thin-walled sleeve (27) having a bottom (32) while being connected to the outer circumference of a reduced end (31) of the piston bottom (19), preferably by a press fit. Furthermore, the hole (34) is located in the bottom (32) of the sleeve and is disposed in an axial direction.