An agricultural harvesting machine (10) includes a chassis (12) and a threshing system (24) carried by the chassis (12). The threshing system (24) includes a rotor (40), a frame assembly (80) and at least one concave (42) carried by the frame assembly (80). A latch mechanism (76) supports and secures the concave (42) relative to the frame assembly (80) and includes a concave support bar (72), a clamping bar (74) and a quick-connect, over center latch (92) for tool-less operation.
