This is a really easy-to-use and super handy prototyping plate.  Basically you can put everything from an Arduino board to sensors, and even a motor on top of it.  It fits M2-M3 screws.

NOTE: This product does not ship with the board shown above.  Please check the package list below for reference.

Specifications:

• Size: 170x150mm
• Slot size: 3mm
• Total weight: 350g (including all screws)

Package Includes:

• Prototyping Plate (1 unit)
• M3 screw set (50 units)
• M3 * 10 Hexagonal Copper standoffs (10 units)
• M3 * 10 Hexagonal Nylon standoffs (10 units) 
• M3 * 20 Hexagonal Nylon standoffs (10 units) 
• M3 * 30 Hexagonal Copper standoffs (10 units)
• M3 * 50 Hexagonal Copper standoffs (10 units)