Features: Material: Aluminum Size: Approx. 8.5 x 8.5 x 5mm/0.34 x 0.34 x 0.20inch The Aluminium Heatsink is specially designed for Raspberry Pi The function of heat sink is to cool down the board and make your Raspberry operate better This 8.5 x 8.5 x 5mm heatsink use with the A4988 drivers Heatsink for A4988 StepStick Stepper Motor Driver Module 3D Printer Reprap RAMPS，etc. Note: This product has no adhesivePackage Included: 10x Heatsink