There are several posts about Williams Fire Sights on Rem870.com:
Williams Gun Sight Company: Remington 870 Universal Ghost Ring Firesights
Williams Gun Sight Company: Remington 870 Fiber Optic ACE IN THE HOLE Sight Review
Remington Ghost Ring Firesight Set by Williams Gun Sight Company, Inc.

I decided to try another type of Williams Fire Sights on my Remington 870 with rifle sights:

Williams Fire Sights on for Remington 870

Williams Fire Sights on for Remington 870

Williams Gun Sight Co. manufactures a lot of different sights for different types of guns. And Remington 870 with rifle sights enables you to replace standard sights easily. You just push out the front sight using brass punch and then install the new one. Dovetail front sight may require some fitting. Also try installing it from different sides, one side may fit better than the other.

Rear sight is even easier to change, just unscre the rear sight windage screw and replace the factor sight aperture with new one.

Remeber to zero new sights after installation.

Williams Fire Sights Front Sight:

Williams Fire Sights Front Sight

Williams Fire Sights Front Sight

Williams Fire Sights Rear Sight

Williams Fire Sights Rear Sight

Williams Fire Sights Rear Sight

This shotgun sights set is really good and very well made. The sights are made of aluminum with fiber optic light gathering inserts. There are thousands of happy users of these sights and they really make life of a shotgun owner easier.

If you like to shoot slugs then you are going to like this set of sights. They make it much easier to shoot slugs accurately especially on long distances. There are sights not only for Remington 870 shotgun but for other guns too: Ruger 10/22, AR-15, SKS, Marlin, etc.

Advantages:
-Bright sights make it easier to shoot faster and accurately
-Inexpensive
-Easy to install

Disadvantages:
-Fiber optic elements are can be easily damaged

Remington 870 Front and Rear Rifle Sights Installation and Removal Video Instructions

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