Created for us folk who have aged eyesight, this sight has a extra wide (.170" wide x .125" deep) rear sight notch. My intention was to use this in conjunction with the Trijicon HD front sight that I offer. Together, they combine to give a larger sight picture with lots of daylight on each side of the front sight blade which will let you a more clear focus on your sight picture than you've had in many years.
Fits slides machined for the .500" x 65° Novak Lo-Mount sight cut. The HD-004 sights are .325" tall at the rear blade, which is the standard Novak height. If you need the taller .375" tall version, see my HD-005-WU.