Progressive metal outfit Watchtower have released a teaser for their upcoming single “Mathematica Calculis”. The song is a previously unreleased track that is set to appear on the group’s upcoming Concepts Of Math: Book One EP, their first output in over 20 years. Prosthetic Records will have the effort in stores official on October 7th.

Due to popular demand, a third pressing of silver LPs have been added and are now available for pre-order along with CD versions of the effort through the label’s webshop. For European pre-orders, follow this link.