ProShares Ultra S&P500 SSO ETF

The SSO is an ETF managed by ProShares, an investment fund manager. This ETF seeks a return of 200% of the return of the S&P500 index for a single day. (Note: compounding effects will make the multi-day return different.)

Compare this to ProShares UltraShort S&P500 SDS ETF.

ProShares' official page on the SSO:
http://www.proshares.com/funds/sso.html

Ticker: SSO
Intraday Ticker: SSO.IV
CUSIP: 74347R107
Inception Date: 6/19/06
Expense Ratio: 0.95%
NAV Calculation Time: 4:00 p.m. ET