sudo dd if=gpt/tests/fixtures/test.img bs=512 count=1 skip=1 > lba.1
Primary Header of test.img
------------------------------------------
Signature:              0x4546492050415254
Revision:                       0x00000100
HeaderSize:                             92
HeaderCRC32:                    0x24929e70
HeaderCRC32 (calculated):       0x24929e70
Reserved:                       0x00000000
MyLBA:                                   1
AlternateLBA:                        20479
FirstUsableLBA:                       2048
LastUsableLBA:                       20446
PartitionEntryLBA:                       2
NumberOfPartitionEntries:              128
SizeOfPartitionEntry:                  128
PartitionEntryArrayCRC32:       0xd9c4150d

==========================================
sudo dd if=gpt/tests/fixtures/test.img bs=512 count=1 skip=20479 > lba.last
Backup Header
------------------------------------------
Signature:              0x4546492050415254
Revision:                       0x00000100
HeaderSize:                             92
HeaderCRC32:                    0x9e29fd39
HeaderCRC32 (calculated):       0x9e29fd39
Reserved:                       0x00000000
MyLBA:                               20479
AlternateLBA:                            1
FirstUsableLBA:                       2048
LastUsableLBA:                       20446
PartitionEntryLBA:                   20447
NumberOfPartitionEntries:              128
SizeOfPartitionEntry:                  128
PartitionEntryArrayCRC32:       0xd9c4150d