If you want a smaller peep hole, I think the Millet is the only one besides the Ram Line $5 plastic "hooded" sight from Delta Force that only replaces the leaf. I bought the latter but didn't even put it on my gun; it was so terrible. After that, I had greater apprecitaion for the factory sight. However, size shouldn't matter anyway because on peep sights, the only requirement is you look through the aperture and focus on the front. I believe the hole can actually be increased with very little effect on accuracy. Ashley/XS sight systems makes a nice rear Ghost Ring sight blade for around $25 that I will probably end up getting one of these days because it looks a little more mil-spec and should speed up target aquisition time.