A sterile adapter for coupling a surgical instrument and a surgical instrument manipulator includes a bottom component and a coupling component. The bottom component includes a bottom component opening with a bottom lip having a locking mechanism. The coupling component is rotatably coupled to the bottom component. The coupling component includes an engagement feature that engages the surgical instrument manipulator. The coupling component further includes a locking mechanism opening that engages the locking mechanism when the engagement feature has not engaged the surgical instrument manipulator. The coupling component may include a retention tab that is aligned with the keyway to insert the coupling component into the bottom component opening and then misaligned with the keyway to retain the coupling component in the bottom component opening. A ramp may be provided on a leading edge of a pocket to facilitate engaging the coupling component with the surgical instrument manipulator.
