Polaris Anzen Metal Spa Blower 110V - 1 HP. The rugged all-steel construction of the Polaris Metal Blowers has been an industry standard. The unique, patented thermal relief valve automatically compensates for temporary rises in temperature so the blower motor doesn't get hot enough to reach the shutoff point. This means longer, more relaxing, uninterrupted service.. Polaris also offers a full line of metal residential blowers. This is the bottom mount.