Two-by-Two or Two-by-One

Two-by-Two or Two-by-One

Lengths of wood used in the construction of the set. The two numbers refer to the wood's cross section (short dimensions). e.g: 2 by 2 is wood of any length which has a 2" by 2" cross section. (Imperial units are common in set construction)

Also, you should take care when working with it, as the wood is often not exactly 2" by 2". This can be because it has been planed smooth, or because it was actually measured in metric units. When you're building sets it always pays to check the exact dimensions of the wood.