To my knowledge (and I may be wrong) they don’t believe in transubstantiation.
Here is what Luther wrote:
Who, but the devil, has granted such license of wresting the words of the holy Scripture? Who ever read in the Scriptures, that my body is the same as the sign of my body? or, that is is the same as it signifies? What language in the world ever spoke so? It is only then the devil, that imposes upon us by these fanatical men. Not one of the Fathers of the Church, though so numerous, ever spoke as the Sacramentarians:not one of them ever said, It is only bread and wine; or, the body and blood of Christ is not there present.
Surely, it is not credible, nor possible, since they often speak, and repeat their sentiments, that they should never (if they thought so) not so much as once, say, or let slip these words: It is bread only; or the body of Christ is not there, especially it being of great importance, that men should not be deceived. Certainly, in so many Fathers, and in so many writings, the negative might at least be found in one of them, had they thought the body and blood of Christ were not really present: but they are all of them unanimous." - Luther's Collected Works, Wittenburg Edition, no. 7 p, 391