BVOL tokens are ERC20 tokens that attempt to track the implied volatility of crypto markets. Each BVOL token gets its price action by trading FTX MOVE contracts. For instance, say that you want to create $10,000 of BVOL. To do so you can send in $10,000, and the BVOL account on FTX buys $10,000 worth of FTX MOVE contracts. Thus, BVOL is now 1x long MOVE.

You can also redeem BVOL tokens for their net asset value. To do that, you can send your $10,000 of BVOL back to FTX, and redeem it. This will destroy the token; cause the BVOL account to sell back the $10,000 worth of MOVE contracts, and credit your account with $10,000.

This creation and redemption mechanism is what ultimately enforces that the leveraged tokens are worth what they're supposed to be.