The C1 is an A1 length (5/8" shorter than an A2 stock) fixed buttstock.  The shorter length of pull makes it well suited for use with heavy clothing, body armor, and by shooters of smaller stature.  Many also prefer it because it allows the shooter to more easily assume a "nose to the charging handle" cheek weld"

The C1 has a larger trap door compartment than that of other AR15 buttstocks, because the buffer tube channel and trap door compartment are formed in the mold.  The sling swivel can be offset to either left or right in addition to straight down.

The C1 is injection molded from glass filled nylon 6, and comes with our injection molded buttplate/ trap door, sling swivel, and shorter screw.  (Most manufacturer's A1/A2 buttplate assemblies will work with the C1.)