This is a used tilt mechanism from a Classic Herman Miller Aeron, Size C, Graphite. This mechanism is untested, and I cannot confirm whether any of the tilt functions work tilt lock, tension, limiter, etc. Given the age, assume it may need service and may have internal issues. Covers/trim: the plastic mechanism covers are still attached, but they are separating and should be considered broken/brittle. What you see is what you get. No additional hardware or parts included.