Here it is, the secret to the squeeze—half of the pair of sensors responsible for detecting when you squeeze the edge of your Pixel 2 XL.

The sensor consists of a flexible printed circuit board wrapped around both sides of a line of steel chunks, with strain gauges bridging the gaps between the metal bits.

Strain gauges are deformation-sensitive resistors, that slightly change their resistance when stretched or squished.

Having two rows of strain gauges separated by spacers should give this sensor higher resolution than a single strip of gauges would, allowing it to detect even the slightest of deflections.

As you squeeze, the outer row of gauges should be shortened, while the inner row is lengthened. This gives the Pixel software a larger absolute deflection to detect and measure to trigger the feature.