Not as bright as real tritium sights - Blitzkrieg Components AR Spike Front Sight Post

Fits correctly into a standard mil-spec front sight post. The shape and color are accurate to the picture. The "Luminescent Contrast Stripe" works but only after "charging" it for a couple of seconds with a bright light aimed directly into it at close range. So it's "luminescent" in that way, and is really bright after absorbing light from another source, but don't expect to be able to use these in any real low light scenario like a set of TruGlo/Tritium sights.

The colored front post can help for some people in acquiring a sight picture, so I recommend it for that, but if you're looking for a something for real low light scenarios, this is probably not it.