Mutual funds that invest in the least risky municipal bonds. These bonds are rated single A to triple A, but they are not insured.
UNINSURED HIGH-QUALITY MUNICIPAL BOND FUNDS
Meaning of UNINSURED HIGH-QUALITY MUNICIPAL BOND FUNDS in English
Mutual Fund English Glossary. Английский глоссарий взаимных и инвестиционных фондов. 2012