"The LEGO® Technic™ Force Sensor measures pressures of up to 10 Newtons (~1kg) for accurate, repeatable results. The sensor can also be used as a touch sensor when pressed, released or bumped.
• Measures up to 10 Newtons (~1kg).
• Doubles as a touch sensor with pressed/released/bumped detection.
• Simple form factor for quick building and rebuilding."