The Low Profile 8-40 Sight fits all marlin rifles and usually works with the factory front sight. Elevation adjustment is made by turning the stem and locking it in place with the knurled lock nut.
It has no windage adjustment other than that offered by drifting the front sight. It mounts in any of the drilled and tapped holes on top of the receiver.
This sight comes standard with a .096″ aperture. Other size apertures are available.