A mechanism (30) for a lockset (10); the mechanism (30) comprises a latchbolt retractor (22) that is rotationally actuatable. The mechanism (30) also comprises a rotationally mounted handle coupler (36). The rotationally mounted handle coupler (36) is rotatable by a rotation of a handle (12) when coupled thereto and comprises an adaptor receiver (46) for receiving any one of a plurality of adaptors (48,52,54). The rotationally mounted handle coupler is configured to engage with at least one of the plurality of adaptors (48,52), but not all of the plurality of adaptors (54), for transmission of the rotation of the handle (12) to a latchbolt retractor actuator (22).