SUIT Shooter Usually in trouble, love it.............long time ago and a lot of sights under the bridge to remember all details but I do remember the parts.
The sight had a fixed plate on the top cover, which you then could detach the sight by turning two knobs by hand.
To refit the reverse, with a spring loaded spigot, popping up in the middle of the two knobs and locking it in position very clever for the day