Perhaps it's time to ditch the thinking that money market and stable value funds are the only major cash preservation vehicles.

San Francisco'sCharles Schwab Investment Managementemerges as yet another firm seeking an alternative to traditional preservation methods, filing for an actively managed ETF that specifically seeks capital preservation and daily liquidity.

TheSchwab Active Short Duration Income ETFwill bet mostly on short-term investments including investment grade short-term fixed-income securities by U.S. and foreign issuers. It may not invest more than 15% of its net assets in illiquid securities.

Linda Klingman, managing director and head of taxable money market strategies, will manage the fund. Its distributor is Oaks, Penn.-basedSEI Investments.

Because the ETF is actively, rather than passively, managed, it may have a higher turnover rate compared to index funds.