you could choose a natural stone surround, but that will be a bit pricier. Also, on the high end, consider a solid surface or quartz surround for low-maintenance options. Here is a cost comparison of some of the most common materials used for tub surrounds, assuming a size of 60 inches...
Air Manifold -- The manifold is the piping that surrounds the tub on the bottom, the sides or both and is usually hidden by a decorative frame. When air from the pump enters the manifold, it fills the entire space, which could have single or multiple channels, and is forced through very...