Saw what appeared to be a clip-on front sight on an 870 that consisted of about 2 inches of 1/8 inch diameter clear yellow plexiglas. Seemed awfully good for a quick snap shot...
a la "whatch the front sight". Anyone familiar with this? pros/cons ?       Stay safe

I snapped one on the short barrel for my 870 and like it.

It does seem to shoot a little low though. I think it's because of the larger size of the bead. Shouldn't be much of a concern from "across the room" range. Center of mass will still be center of mass.

These really pick up the light, but you have to have some light to pick up. In total darkness, or pretty close to it, they aren't any better than the standard brass bead already on the barrel.

Thank you Troy, et al. That's the one I saw.
Now why don't they make a model with a bit of glow-in-the-dark tritium underneath to illuminate it in any light conditions? Stay safe