I think he wants to know how to access the struct/record elements.

As Micheus explained, both reference the same memory. The only difference is how they treat that memory.

bp thinks the memory is just a list of bytes.

pTcpHdr thinks the memory is a record containing information about a Tcp Packet (and it would be right). I was careful in the example not to change the pTcpHdr variable, so you can still access the packet header by dereferencing it: pTcpHdr^.Options := 42;

Hope this helps.