Factory HK sights slide into the slot on the top of the sight tower and are roll pinned in place.  Other aftermarket HK sights install in a similar fashion using the roll pin.  This installation method limited sight design and required a roll pin to be hammered into the bottom of the sight.  We came up with a better way to do it.  To install our Blitzkrieg Gen 2 HK and PTR front sights, you drive out the roll pin far enough to remove the old sight, then drive the roll pin back in.  Then you can do the rest by hand with no tools.  Simply drop in our sight flange into the slot and it has a notch that rests on the roll pin.  Then insert the sight reticle from the muzzle side of the sight and thread on the lock ring from the receiver side of the sight and your done.  There are instructions included with each sight that explain the process in more detail.  But it is simple to do.  Once our sight is installed, the sight reticles can be changed out for other Blitzkrieg reticle designs in minutes without tools.  We are adding more reticle designs as we move forward that will be available separately.  This system results in a superior sight picture, more available sight design options and a modular system.  

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