A flexible coupler apparatus (10) for joining successive lengths of pipe in an exhaust system for a vehicle. An inner sleeve member (17) is concentrically received by an outer sleeve member (16). A substantially porous, non-sealing, vibration absorbing spacer member (48) is arranged between the sleeve members (16,17) where they overlap, to preclude direct contact between the sleeve members (16,17). The spacer member (48) is non-sealing to preclude deterioration while minimizing interference with the reciprocation and articulation of the sleeve members (16,17). A flexible, extensible member (22) mechanically connects the sleeve members (16,17) at their distant non-overlapped ends. A closure member (23) may be employed to protect the extensible member (22) from damage from external elements and forces.