The 56 Frame Thru Bolt spa motor has the same durability, moisture resistance and energy efficiency as the 48 Frame Thru Bolt and also offers both single speed and two speed options. It differs from the 48 Frame in that it provides HP options running from 1 1/2 up to 5 THP. In need of Class F insulation, Class B Temperature Rise, sealed ball bearings and thermal protection. This reliable and energy-efficient spa motor is designed to meet these specifications as well.