One set get all buliding pc computer screws:Set included:1:hard drive screws;2:fan;3:Motherboard fixed screws; 4:motherboard standoffs with brass and iron two types; 5:M3 washer;6:Chassis screw;7:thumb screw 8:CD-ROM set screws Package:4pcs Thumb screw(#6-32x6mm) , 20pcs Chassis screw (#6-32x6mm), 20pcs screws for hard drive(#6-32x5BM) 20pcs case screw for motherboards fixed screw(M3x6) , 10pcs case fan screw (5x10KB)