MM Studio Class 100 Accessory have both required and extra components in this listing. Required components are the PCB and plate which may also be purchased as optional extras. MM Studio Class 100 Accessory Features: PCB: Wired Hotswap or Solder Plate: Full Plate: Retro Dyed PC, Aluminum, Brass, Copper Half Plate: Aluminum Bikini Plate: Aluminum Extra Accessories: Extra Screws Extra Feet Extra Force Break Pads Extra Top Mount Parts Extra Solenoid & Buzzer Daughterboard Extra Foam Kit: 3.5mm Poron Plate Foam, 0.5mm PE Sheet, 1.5mm Poron Bottom Case Foam Brass Anodized Aluminum Top Accent Compatible with: MM Studio Class 100 Keyboard Includes: 1 MM Studio Class 100 Accessory