Bundles are groups of Testnet NFTs for sale on OpenSea. You can buy them all at once in one transaction, and you can create them without any transactions or gas, as long as you've already approved the NFTs inside.
As of May 25, this endpoint will return orders from the Seaport contract in the
seaport_sell_orders field. The
sell_orders field will return orders from the Wyvern contract only. Please refer to the Seaport Order model for schema details.