A disability insurer has obtained a new source of financing.

Units of Wachovia Corp., Charlotte, N.C., and Bank of America Corp., Charlotte, have established a $400 million revolving credit facility for Unum, Chattanooga, Tenn.

The facility, which is not secured by any specific assets, resembles the corporate version of a credit card account.

“Completing this facility despite the current difficult environment for financial companies is a strong endorsement of Unum and further evidence of the growing market confidence in our company,” Robert Greving, the company’s chief financial officer, says in a statement.

Unum will use any money drawn from the credit facility for general corporate purses, the company says.

The company notes that it has retired $752 million in debt this year.