What does the 'U' suffix mean at the end of the ATS48 Soft Starters' part numbers?

搜尋常見問題

To order in the US with English only literature, the part number was changed for a short period of time to include the U suffix.
There is no difference in products ordered with U and without U suffix. Customers will get the same product.
The suffix U is no longer used to order this part number.