Our product, the AR15 Free-Floating RS Series Titanium Rail /Barrel Retainer System provides a barrel assembly and rail assembly that is detachable without tools from the main body of a rifle. This is an advantage for field breakdown or modification to the rifle. The user has the option to disassemble the rifle for easy transport, to change barrel length, to change barrel caliber or change rail configurations. The rails are free-floating, meaning the rails do not come in contact with the barrel and thus do not impact the precision of the rifle.