What are the main differences between Reformed Protestant Biblical Theology and Covenant Theology?

I have mostly studied theology by people who have their views labeled as Covenant Theology, by the label makers. Recently, I have studied views of some who prefer the label, Biblical Theology. I have noticed differences between the two but have not attempted to put those differences into words. My question is, 'What are the main differences between Reformed Protestant Biblical Theology and Covenant Theology ?' I am not asking about Systematic Theology as this label seems to speak more about style rather than content. I am asking about differences in actual belief, not style.