I had emailed John over 2 years ago (well before this sight was released) regarding replacement fixed rear sights for my Ruger SR1911 10mm. He confirmed what I found on the interwebs: while Ruger has a Bomar-ish cut for their SR1911s with adjustable rear sights, it is a proprietary cut! I had even emailed the company that makes Ruger's adjustable rear sights. In no uncertain words, they confirmed this sight and sight cut was unique to the Ruger AND they had ZERO plans to make a compatible fixed rear "combat " sight. Dejected, I settled with replacing the horrible all-black Ruger front sight with a tritium front sight. During this adventure, John had-of his own volition-emailed me photos of customers who had fit fixed sights to their SR1911s. I was contemplating this pursuit but put it on the back burner as "it would be cool, but not essential right now".
To my absolute delight, around 6 months later, I got an email from John announcing fixed Ruger rear sights for the SR1911 were available for pre-order! Needless to say, my $$$ was out the door and soon enough, I had the sight installed! Its now been carried through 2 elk hunting seasons and I love its low, smooth profile. I am just not a fan of adjustable rear sights with their square, protruding profile. This sight is solid!
Thank you a thousand times over Harrison Design for not only making quality products but listening to customer inquiries. No one else has bothered (to my knowledge) offering replacement rear sights for this Ruger model.