Crucifixion - torture stake or cross?

The Jehovah's Witnesses state that Jesus was not nailed on a cross, but on a torture stake. The New World Translation of the Bible is phrased accordingly. For example: > **Matthew 10:38 (NWT)** > And whoever does not accept his torture stake and follow after me is not worthy of me. (All the other translations (that I know of) translate *cross* instead.) What is significant about the difference between a **torture stake** and a **cross**, and on which one was Jesus crucified? --- An illustration of what might be a *torture stake:*