diff --git a/db/prefixes/prefixes.go b/db/prefixes/prefixes.go
index 2c5d886..39cda6d 100644
--- a/db/prefixes/prefixes.go
+++ b/db/prefixes/prefixes.go
@@ -245,13 +245,85 @@ class BlockHeaderValue(NamedTuple):
 
 type BlockHeaderKey struct {
 	Prefix []byte `json:"prefix"`
-	Height int32  `json:"height"`
+	Height uint32 `json:"height"`
 }
 
 type BlockHeaderValue struct {
 	Header []byte `json:"header"`
 }
 
+func (k *BlockHeaderKey) PackKey() []byte {
+	prefixLen := 1
+	// b'>L'
+	n := prefixLen + 4
+	key := make([]byte, n)
+	copy(key, k.Prefix)
+	binary.BigEndian.PutUint32(key[prefixLen:], k.Height)
+
+	return key
+}
+
+func (v *BlockHeaderValue) PackValue() []byte {
+	value := make([]byte, 112)
+	copy(value, v.Header)
+
+	return value
+}
+
+func BlockHeaderKeyPackPartialNFields(nFields int) func(*BlockHeaderKey) []byte {
+	return func(u *BlockHeaderKey) []byte {
+		return BlockHeaderKeyPackPartial(u, nFields)
+	}
+}
+
+func BlockHeaderKeyPackPartial(k *BlockHeaderKey, nFields int) []byte {
+	// Limit nFields between 0 and number of fields, we always at least need
+	// the prefix, and we never need to iterate past the number of fields.
+	if nFields > 1 {
+		nFields = 1
+	}
+	if nFields < 0 {
+		nFields = 0
+	}
+
+	// b'>4sLH'
+	prefixLen := 1
+	var n = prefixLen
+	for i := 0; i <= nFields; i++ {
+		switch i {
+		case 1:
+			n += 4
+		}
+	}
+
+	key := make([]byte, n)
+
+	for i := 0; i <= nFields; i++ {
+		switch i {
+		case 0:
+			copy(key, k.Prefix)
+		case 1:
+			binary.BigEndian.PutUint32(key[prefixLen:], k.Height)
+		}
+	}
+
+	return key
+}
+
+func BlockHeaderKeyUnpack(key []byte) *BlockHeaderKey {
+	prefixLen := 1
+	return &BlockHeaderKey{
+		Prefix: key[:prefixLen],
+		Height: binary.BigEndian.Uint32(key[prefixLen:]),
+	}
+}
+
+func BlockHeaderValueUnpack(value []byte) *BlockHeaderValue {
+	return &BlockHeaderValue{
+		Header: value[:112],
+	}
+}
+
 /*
 
 class ClaimToTXOKey(typing.NamedTuple):
@@ -295,7 +367,7 @@ type ClaimToTXOValue struct {
 }
 
 func (v *ClaimToTXOValue) NormalizedName() string {
-	//TODO implement
+	//TODO implement? Might not need to do anything.
 	return v.Name
 }
 
@@ -2519,8 +2591,11 @@ func UnpackGenericKey(key []byte) (byte, interface{}, error) {
 
 	case Tx:
 	case BlockHash:
+		return 0x0, nil, errors.Base("key unpack function for %v not implemented", firstByte)
 	case Header:
+		return Header, BlockHeaderKeyUnpack(key), nil
 	case TxNum:
+		return 0x0, nil, errors.Base("key unpack function for %v not implemented", firstByte)
 	case TxCount:
 	case TxHash:
 		return 0x0, nil, errors.Base("key unpack function for %v not implemented", firstByte)
@@ -2590,8 +2665,11 @@ func UnpackGenericValue(key, value []byte) (byte, interface{}, error) {
 
 	case Tx:
 	case BlockHash:
+		return 0x0, nil, errors.Base("value unpack not implemented for key %v", key)
 	case Header:
+		return Header, BlockHeaderValueUnpack(value), nil
 	case TxNum:
+		return 0x0, nil, errors.Base("value unpack not implemented for key %v", key)
 	case TxCount:
 	case TxHash:
 		return 0x0, nil, errors.Base("value unpack not implemented for key %v", key)
diff --git a/db/prefixes/prefixes_test.go b/db/prefixes/prefixes_test.go
index 59ec3f0..d2ef1a6 100644
--- a/db/prefixes/prefixes_test.go
+++ b/db/prefixes/prefixes_test.go
@@ -44,6 +44,82 @@ func testInit(filePath string) (*grocksdb.DB, [][]string, func()) {
 	return db, records, toDefer
 }
 
+func TestBlockHeader(t *testing.T) {
+
+	filePath := "../../resources/header.csv"
+
+	wOpts := grocksdb.NewDefaultWriteOptions()
+	db, records, toDefer := testInit(filePath)
+	defer toDefer()
+	for _, record := range records {
+		key, err := hex.DecodeString(record[0])
+		if err != nil {
+			log.Println(err)
+		}
+		val, err := hex.DecodeString(record[1])
+		if err != nil {
+			log.Println(err)
+		}
+		db.Put(wOpts, key, val)
+	}
+	// test prefix
+	options := dbpkg.NewIterateOptions().WithPrefix([]byte{prefixes.Header}).WithIncludeValue(true)
+	ch := dbpkg.Iter(db, options)
+	var i = 0
+	for kv := range ch {
+		// log.Println(kv.Key)
+		gotKey := kv.Key.(*prefixes.BlockHeaderKey).PackKey()
+
+		keyPartial1 := prefixes.BlockHeaderKeyPackPartial(kv.Key.(*prefixes.BlockHeaderKey), 1)
+
+		// Check pack partial for sanity
+		if !bytes.HasPrefix(gotKey, keyPartial1) {
+			t.Errorf("%+v should be prefix of %+v\n", keyPartial1, gotKey)
+		}
+
+		got := kv.Value.(*prefixes.BlockHeaderValue).PackValue()
+		wantKey, err := hex.DecodeString(records[i][0])
+		if err != nil {
+			log.Println(err)
+		}
+		want, err := hex.DecodeString(records[i][1])
+		if err != nil {
+			log.Println(err)
+		}
+		if !bytes.Equal(gotKey, wantKey) {
+			t.Errorf("gotKey: %+v, wantKey: %+v\n", got, want)
+		}
+		if !bytes.Equal(got, want) {
+			t.Errorf("got: %+v, want: %+v\n", got, want)
+		}
+		i++
+	}
+
+	// Test start / stop
+	start, err := hex.DecodeString(records[0][0])
+	if err != nil {
+		log.Println(err)
+	}
+	stop, err := hex.DecodeString(records[9][0])
+	if err != nil {
+		log.Println(err)
+	}
+	options2 := dbpkg.NewIterateOptions().WithStart(start).WithStop(stop).WithIncludeValue(true)
+	ch2 := dbpkg.Iter(db, options2)
+	i = 0
+	for kv := range ch2 {
+		got := kv.Value.(*prefixes.BlockHeaderValue).PackValue()
+		want, err := hex.DecodeString(records[i][1])
+		if err != nil {
+			log.Println(err)
+		}
+		if !bytes.Equal(got, want) {
+			t.Errorf("got: %+v, want: %+v\n", got, want)
+		}
+		i++
+	}
+}
+
 func TestClaimToTXO(t *testing.T) {
 
 	filePath := "../../resources/claim_to_txo.csv"
diff --git a/main.go b/main.go
index 90e8d42..2943ebf 100644
--- a/main.go
+++ b/main.go
@@ -38,7 +38,7 @@ func main() {
 
 		options := &db.IterOptions{
 			FillCache:    false,
-			Prefix:       []byte{prefixes.ClaimToTXO},
+			Prefix:       []byte{prefixes.Header},
 			Start:        nil,
 			Stop:         nil,
 			IncludeStart: true,
@@ -49,7 +49,7 @@ func main() {
 			RawValue:     true,
 		}
 
-		db.ReadWriteRawN(dbVal, options, "./resources/claim_to_txo.csv", 10)
+		db.ReadWriteRawN(dbVal, options, "./resources/header.csv", 10)
 
 		return
 	}
diff --git a/resources/header.csv b/resources/header.csv
new file mode 100644
index 0000000..74946c8
--- /dev/null
+++ b/resources/header.csv
@@ -0,0 +1,10 @@
+4800000000,010000000000000000000000000000000000000000000000000000000000000000000000cc59e59ff97ac092b55e423aa5495151ed6fb80570a5bb78cd5bd1c3821c21b8010000000000000000000000000000000000000000000000000000000000000033193156ffff001f07050000
+4800000001,0000002063f4346a4db34fdfce29a70f5e8d11f065f6b91602b7036c7f22f3a03b28899cba888e2f9c037f831046f8ad09f6d378f79c728d003b177a64d29621f481da5d01000000000000000000000000000000000000000000000000000000000000003c406b5746e1001f5b4f0000
+4800000002,00000020246cb85843ac936d55388f2ff288b011add5b1b20cca9cfd19a403ca2c9ecbde09d8734d81b5f2eb1b653caf17491544ddfbc72f2f4c0c3f22a3362db5ba9d4701000000000000000000000000000000000000000000000000000000000000003d406b57ffff001f4ff20000
+4800000003,000000200044e1258b865d262587c28ff98853bc52bb31266230c1c648cc9004047a5428e285dbf24334585b9a924536a717160ee185a86d1eeb7b19684538685eca761a01000000000000000000000000000000000000000000000000000000000000003d406b5746e1001fce9c0100
+4800000004,00000020bbf8980e3f7604896821203bf62f97f311124da1fbb95bf523fcfdb356ad19c9d83cf1408debbd631950b7a95b0c940772119cd8a615a3d44601568713fec80c01000000000000000000000000000000000000000000000000000000000000003e406b573dc6001fec7b0000
+4800000005,000000201a650b9b7b9d132e257ff6b336ba7cd96b1796357c4fc8dd7d0bd1ff1de057d547638e54178dbdddf2e81a3b7566860e5264df6066755f9760a893f5caecc57901000000000000000000000000000000000000000000000000000000000000003e406b5773ae001fcf770000
+4800000006,000000206d694b93a2bb5ac23a13ed6749a789ca751cf73d5982c459e0cd9d5d303da74cec91627e0dba856b933983425d7f72958e8f974682632a0fa2acee9cfd81940101000000000000000000000000000000000000000000000000000000000000003e406b578399001f225c0100
+4800000007,00000020b57808c188b7315583cf120fe89de923583bc7a8ebff03189145b86bf859b21ba3c4a19948a1263722c45c5601fd10a7aea7cf73bfa45e060508f109155e80ab01000000000000000000000000000000000000000000000000000000000000003f406b571787001f08160700
+4800000008,00000020a6a5b330e816242d54c8586ba9b6d63c19d921171ef3d4525b8ffc635742e83a0fc2da46cf0de0057c1b9fc93d997105ff6cf2c8c43269b446c1dbf5ac18be8c010000000000000000000000000000000000000000000000000000000000000040406b570ae1761edd8f0300
+4800000009,00000020b8447f415279dffe8a09afe6f6d5e335a2f6911fce8e1d1866723d5e5e8a53067356a733f87e592ea133328792dd9d676ed83771c8ff0f519928ce752f159ba6010000000000000000000000000000000000000000000000000000000000000040406b57139d681ed40d0000