sentences:  More modern cases from certain manufacturers (Dell, Gateway) and enthusiast cases will lack screws altogether, instead utilizing a tool-less design.The #6-32 UNC is a UTS screw specifying a major thread diameter of which is defined as ; and (threads per inch) which equates to a thread pitch of .The optional UNC specification indicates the standard coarse thread is used which is defined for #6 screws as 32 tpi rendering 'UNC' redundant, however it may be seen when other specifications such as plating or other treatments are also specified.