Credit Suisse halted further creation of new TVIX shares in February due to internal limits on the size of the ETN.

Unlike exchange traded funds, ETNs are debt instruments issued by financial institutions that promise to pay the return of an index. Therefore, they introduce credit risk.

TVIX and other volatility-linked products are designed to track VIX futures contracts — not the spot price.

These funds can be hurt by so-called contango in VIX futures markets. [VIX ETFs: Beware Contango]

TVIX is linked to 200% of the daily performance of the S&P 500 VIX Short-Term Futures Index, minus fees. TVIX’s market cap was hovering around $400 million on Thursday afternoon following the steep decline, according to MarketWatch data.

ProShares Ultra VIX Short-Term Futures ETF (NYSEArca: UVXY), an exchange traded fund with a similar goal as TVIX, gained 2% on Thursday and has seen trading volume rise in recent weeks.

VelocityShares Daily 2x VIX Short-Term ETN