Instruction: Given a question and its related document, determine if the question is answerable by analyzing the information in the document. Output yes if the document addresses the question, or no otherwise.

Input:
Question: Does any one know the actual length of this sight?
Document: This has to be the simplest repair/replacement for a front shotgun bead...EVER! I have several old shotguns on which the barrels have been cut down for various reasons (damage, shorten to &#34;defense shotgun&#34; length, etc.). Instead of drilling and tapping for a new bead, I simply pop one of these fibeer optic sights on the barrel (the unit fits both 12 or 20 gauge). Excellent visibility.
I don't know why, but I had the idea this sight was metal instead of plastic -- reading too many reviews, I guess. It really IS a good thing that it is plastic, though, because it gives it less momentum to pull it off the barrel when the gun fires.
snaps on barrel has good contrasts i have not actualy fired the gun yet so i do not know if it moves after being fired als had a great price.
Easy to install. Very easy to see. Huge improvement over the stock sight. I bought this sight along with several other accessories, and this is one of the best. I changed the green out to red (which comes with it). Love it!
This sight really jumps out at you. It is so bright that it is very easy to acquire a good sight picture. After repeated shooting it does shift around a little bit but moves back into position quickly. Anyone looking for a cheap shotgun sight should take a serious look at this one.
I received it with the large green sight in it, which would not for the life of me come out even using the instructions. Eventually I got it out by having the larger end break off, so now I am already down to 3 tubes after just receiving it. I'm a little pissed off with this one, as it was pretty ridiculous to "slide it forward" on my barrel after having snapping it on, and it even left scratches on the barrel from attempts to move it.
I bought 2 of these sights. One for my 12 gauge and another for my wife's 20 gauge. Make SURE you have the traditional bead sight on your shotgun. They won't work on any other type of shot gun sight.Installation was nothing more than snapping the sight on and sliding up to the existing bead. You have the option of red or green tubes.The difference between the traditional bead sight and these HiViz sights is astounding.
Got tired of the brass bead and wanted something that would stand out when sighting down range. This snapped right on to the barrel and the little notch on the sight secures the sight behind the brass bead. No gunsmithing required. This thing really makes it to acquire your target and has stayed put through a few hundred rounds. Haven't tried the different colors, but I'm very happy with the big green one that comes installed.
However with my old eyes, I sometimes had trouble getting a good sight picture with a dark target and had to set up my sight picture off the target and swing back to fire. I saw how good the HiViz sight was installed on a gun at a gun show and realized it might solve my problem. I installed it easily yesterday, opening it up at one end with my fingers and then snapping it on and sliding it forward to the bead.
Works very well on my Rossi 12 gauge single shot. I don't like the whole bead sight thing, and this is the easiest way to improve on a stock bead sight for a shotgun.One must be careful changing the tubes, as they can be broken easily with the wrong handling. I found it easier to change tubes by taking it off the gun.I haven't tested it yet for stability in live fire, but it went on easily, is easy to take off and replace, and seems very stable.
Answer: yes