This Yankee Hill Machine Co folding rear sight was designed to be a durable sight that will be there when you need it. It features steel construction securely mounts to your Picatinny rail or flat top receivers via a quick release thumbscrew and aluminum stem.
If you plan on using this as part of your back-up iron sights (BUIS), then you will love how light and compact this rear sight is. When not in use, the sight folds away neatly and only measures 0.840” from the highest point down to the top of the upper receiver. With such a small rear sight, this will give you more option when mounting your primary optic.
This YHM rear sight is standard height for a M16/AR-15. It is designed to be compatible with a standard A2 height front sight. YHM does offer other folding front sights that would work well with this rear sight.