Description : The new SVI II AP (Advanced Performance) positioner uses the identical philosophies and physics of the highly successful, existing SVI II positioner. However, the new SVI II AP positioner enhancements significantly extend the performance level of digital valve positioners to new heights. In addition to performance enhancements, the modular construction and use of many marine grade components have greatly increased the ruggedness and durability of the SVI II AP positioner in harsh environments.
Source : http://www.exionasia.com/indexes.aspx?uc=products_proddetail&ID=91&Page=