You send: Bitcoin Cash (Binance Smart Chain)
Bitcoin Cash split from Bitcoin in 2017 to allow larger blocks and cheaper on-chain payments. It keeps Bitcoin's 21 million supply cap and uses its own address format, CashAddr. More about Bitcoin Cash.
On this pair it moves over BEP20 — an address there starts with 0x — 42 characters.
BCH also exists on other networks — different addresses, not interchangeable: Bitcoin Cash.

