West Texas Intermediate futures for December delivery closed slightly lower Wednesday at just over $77 per barrel and continues residing at its lowest levels since the third quarter of 2011.

Brent crude, the global benchmark, resides just below $81 per barrel and is flirting with four-year lows, but those ominous factoids are not preventing investors from putting new money to work with futures-based oil exchange traded products.

The four largest oil ETFs, including the United States Oil Fund (NYSEArca: USO) and the double-leveraged ProShares Ultra Bloomberg Crude Oil (NYSEArca: UCO), “received a combined $431 million last month, the most since October 2012” and “have seen an inflow of $284.6 million this month as of Nov. 11,” report Moming Zhou and Dan Murtaugh for Bloomberg.

This is not the first time investors have played with fire only to be burned by long oil ETFs. Substantial inflows to USO, UCO and the PowerShares DB Oil Fund (NYSEArca: DBO) were spotted last month, but since Oct. 22 DBO and USO are down an average of 4.4%. [Rushing Back to Oil ETFs]

DBO tracks the DBIQ Optimum Yield Crude Oil Index, which is designed to reflect price action in light sweet crude futures. Over the past month, DBO has hauled in $48.1 million in new assets, a total exceeded by just nine PowerShares ETFs, according issuer data.

Investors have poured into the aforementioned ETFs despite all three laboring in bear markets and with little in the way of positive fundamental catalysts. Over the past three months, UCO has tumbled 35.2%. Increased non-OPEC production, slack demand and OPEC’s dwindling pricing power are all factor seen as pressuring crude prices.