We are moving the drain in our shower so that we can install a prefab shower. We already have the cement dug up. What size and what kind of piping do we need to use for this drain?

You must first pinpoint the exact location of the new drain in relation to the shower base. You will need a 2" trap and raiser installed. If you already have one from the old shower why not simply move it to the new location? Regards, Tom