diff --git a/pkg/storage/donut/data/data_v1/data.go b/pkg/storage/donut/data/data_v1/data.go
index 8069bf9aa..a07e9debe 100644
--- a/pkg/storage/donut/data/data_v1/data.go
+++ b/pkg/storage/donut/data/data_v1/data.go
@@ -28,7 +28,7 @@ type Metadata map[string]string
 
 type DataHeader struct {
 	Key           string
-	Part          int
+	Part          uint8
 	Metadata      Metadata
 	EncoderParams EncoderParams
 }
@@ -41,13 +41,13 @@ const (
 )
 
 type EncoderParams struct {
-	Length    int
+	Length    uint32
 	K         uint8
 	M         uint8
 	Technique EncoderTechnique
 }
 
-func NewHeader(key string, part int, metadata Metadata, encoderParams EncoderParams) DataHeader {
+func NewHeader(key string, part uint8, metadata Metadata, encoderParams EncoderParams) DataHeader {
 	header := DataHeader{}
 	header.Key = key
 	header.Part = part
diff --git a/pkg/storage/donut/data/data_v1/data_test.go b/pkg/storage/donut/data/data_v1/data_test.go
index d246b91cd..2bd05c8b7 100644
--- a/pkg/storage/donut/data/data_v1/data_test.go
+++ b/pkg/storage/donut/data/data_v1/data_test.go
@@ -32,9 +32,8 @@ var _ = Suite(&MySuite{})
 func (s *MySuite) TestSingleWrite(c *C) {
 	var testBuffer bytes.Buffer
 	testData := "Hello, World"
-	testLength := len(testData)
 	encoderParams := EncoderParams{
-		Length:    testLength,
+		Length:    uint32(len(testData)),
 		K:         8,
 		M:         8,
 		Technique: CAUCHY,
@@ -43,7 +42,7 @@ func (s *MySuite) TestSingleWrite(c *C) {
 	metadata["Content-Type"] = "application/octet-stream"
 	metadata["Content-MD5"] = "testing"
 
-	header := NewHeader("testobj", 0, metadata, encoderParams)
+	header := NewHeader("testobj", 1, metadata, encoderParams)
 
 	err := WriteData(&testBuffer, header, bytes.NewBufferString(testData))
 	c.Assert(err, IsNil)