diff --git a/cmd/relayer/main.go b/cmd/relayer/main.go
index 6ecc29d..2733992 100644
--- a/cmd/relayer/main.go
+++ b/cmd/relayer/main.go
@@ -5,13 +5,13 @@ import (
 	"fmt"
 	"math/big"
 	"os"
-	"strconv"
 
 	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/tranvictor/ethashproof"
 	"github.com/tranvictor/ethashproof/ethash"
 	"github.com/tranvictor/ethashproof/mtree"
-	"github.com/tranvictor/ethutils/reader"
 )
 
 type Output struct {
@@ -24,24 +24,23 @@ type Output struct {
 
 func main() {
 	if len(os.Args) < 2 {
-		fmt.Printf("Block number param is missing. Please run ./relayer <blocknumber> instead.\n")
+		fmt.Printf("Block rlp param is missing. Please run ./relayer <blockrlp> instead.\n")
 		return
 	}
 	if len(os.Args) > 2 {
-		fmt.Printf("Please pass only 1 param as a block number. Please run ./relayer <blocknumber> instead.\n")
+		fmt.Printf("Please pass only 1 param as a hex-encoded block rlp. Please run ./relayer <blockrlp> instead.\n")
 		return
 	}
-	number, err := strconv.Atoi(os.Args[1])
+	rlpheader, err := hexutil.Decode(os.Args[1])
 	if err != nil {
-		fmt.Printf("Please pass a number as a block number. Please run ./relayer <integer> instead.\n")
+		fmt.Printf("Please pass a hex as a block rlp. Please run ./relayer <hex> instead.\n")
 		fmt.Printf("Error: %s\n", err)
 		return
 	}
-	fmt.Printf("Getting block header\n")
-	r := reader.NewEthReader()
-	header, err := r.HeaderByNumber(int64(number))
-	if err != nil {
-		fmt.Printf("Getting header failed: %s\n", err)
+	fmt.Printf("Decoding block header\n")
+	var header *types.Header
+	if err := rlp.DecodeBytes(rlpheader, &header); err != nil {
+		fmt.Printf("RLP decoding of header failed: %s\n", err)
 		return
 	}
 
@@ -70,11 +69,6 @@ func main() {
 
 	fmt.Printf("Proof length: %d\n", cache.ProofLength)
 
-	rlpheader, err := ethashproof.RLPHeader(header)
-	if err != nil {
-		fmt.Printf("Can't rlp encode the header: %s\n", err)
-	}
-
 	output := &Output{
 		HeaderRLP:    hexutil.Encode(rlpheader),
 		MerkleRoot:   cache.RootHash.Hex(),
diff --git a/utils.go b/utils.go
deleted file mode 100644
index c6d8240..0000000
--- a/utils.go
+++ /dev/null
@@ -1,26 +0,0 @@
-package ethashproof
-
-import (
-	"github.com/ethereum/go-ethereum/core/types"
-	"github.com/ethereum/go-ethereum/rlp"
-)
-
-func RLPHeader(header *types.Header) ([]byte, error) {
-	return rlp.EncodeToBytes([]interface{}{
-		header.ParentHash,
-		header.UncleHash,
-		header.Coinbase,
-		header.Root,
-		header.TxHash,
-		header.ReceiptHash,
-		header.Bloom,
-		header.Difficulty,
-		header.Number,
-		header.GasLimit,
-		header.GasUsed,
-		header.Time,
-		header.Extra,
-		header.MixDigest,
-		header.Nonce,
-	})
-}