The Double Wrench Quilt Block is fairly easy to identify, but it's often confused with it's cousin the Churn Dash block. And as if that wasn't confusing enough, the Churn Dash is often called the Double Monkey Wrench block.

Double Wrench and Churn Dash are both 9-patch grids, the difference between the designs is in their coloring and in the proportion/scale of the grids.