What it does
Gives you new picatinny rail mount options on your seldom used bayonet lug.  We have found it very useful for mounting things like:

Lights
The SureFire x200 lights have a toggle switch on the back of the light that aligns perfectly with your weak hand index finger. You have to try this to really see how awesome that setup works. No more pressure switches unless you want them!

Vertical Grips
You can mount a grip on a shorty without taking up space on the forearm. This is a really clean way to do this on a REALLY short AR upper - see the pic of a 7" upper with a vertical grip in the gallery below.

Sling Mounting Options

The Cletus preserves all of your sling mounting options, and adds some new ones.  If you combine a Cletus with our ASC (Ambi Sling Connector) and use HK style hooks, you have a single point to two-point convertible sling.

Here are the main choices for the Cletus:

• Option 1:
  You can remount the original stock swivel with the rail in place if you want to...we did this just because we knew someone out there liked the original AR swivel

• Option 2:
  The Big Ring will take any sling connector. Note this is a semi-permanent modification to a Cletus, and provides an extremely strong mount point! (Comes with left from shooter's perspective --- for right handed shooters.)

Super solid and secure:

Slides into place firmly over the bayonet lug and holds the lug fully captive in the machined pocket of the Cletus.  Pins in place using the stock AR pin location (new pin included).  Super tough, you will not have this come off in the field.  Rail measures 3.5" long.  Solid 6061 aluminum, CNC machined, bead blasted, anodized matte black.  100% Made in USA.