The BlackRock Liquidity Funds T-Fund Institutional (TSTXX) is a mutual fund that focuses on providing institutional investors with a highly liquid and low-risk investment option. This fund is managed by BlackRock, one of the largest investment management firms in the world, and aims to maintain a stable net asset value (NAV) of $1 per share. The T-Fund Institutional invests primarily in short-term, high-quality debt securities, making it a suitable choice for investors looking for a conservative and easily accessible investment option.