The NYSE first listed the funds a week ago, but the company did not officially launch its mid- and long-term bond funds until Monday.

Bond EFTs is the segment of the ETF space that has single handedly attracted the most inflow of investment dollars in 2009. According to Morningstar, bond ETFs have absorbed some 52 percent of all inflow year-to-date – that’s $26 billion in new investments in taxable bond ETFs and $2.6 billion in municipal bond ETFs.

Pimco 3-7 Year U.S. Treasury Index Fund (NYSEArca: FIVZ) will track the Merrill Lynch 3-7 Year U.S. Treasury Index and it comes with a price tag of 15 basis points.

The fund fills the gap in the company’s bond offerings lineup. Pimco’s other existing short- to mid-maturity funds include exposure to 1-3 Year duration 7-15 Year duration offerings.

FIVZ is also designed to have low volatility relative to the broader bond markets as well as present a low default risk, according to the company.

Pimco’s newest long-term fund was renamed to Pimco 25+ Year Zero Coupon U.S. Treasury Index Fund (NYSEArca: ZROZ) at inception even though it will still track the same benchmark, the BofA Merrill Lynch Long Treasury Principal STRIPS Index. According to the company, ZROZ was renamed to 25+ Year from 20+ Year to better reflect the duration of the index, which as of Sept. 30 was an average of 25.84 years.

ZROZ provides investors with long-term exposure to interest rate movements. The fund also has an expense ratio of 15 basis points.

While FIVZ goes head-to-head with iShares Barclays 3-7 Year Treasury Bond Fund (NYSEArca: IEI), which has nearly $843 million in assets, ZROZ squares off with the Vanguard Extended Duration Treasury ETF (NYSEArca: EDV), which accounts for some $252.5 million in total assets.

You can read IU.com’s initial coverage of the launch here.