This is a very small solderless breadboard with 170 tie points. This breadboard fits nicely on the Arduino Proto Shield Kit and the Arduino MegaShield Kit (use two of these for the MegaShield).

This breadboard has a strong self-adhesive backing. It also has tabs and notches that allow you to connect multiple boards together.

Dimensions: 1.8" × 1.4"

This mini solderless breadboard is available also in red and in white, but those versions don't have the interlocking tabs/notches.