diff --git a/pkg/oggtag/oggtag.go b/pkg/oggtag/oggtag.go
index df45911..dc43de0 100644
--- a/pkg/oggtag/oggtag.go
+++ b/pkg/oggtag/oggtag.go
@@ -22,7 +22,7 @@ const (
 
 // OggFile holds a head of a file and a tail part conatining last granule.
 type OggFile struct {
-	bufHead, bufTail []byte
+	bufHead, bufLast []byte
 }
 
 // NewOggFile reads a file and returns a new OggFile.
@@ -41,7 +41,7 @@ func NewOggFile(path string) (*OggFile, error) {
 		return nil, err
 	}
 
-	of.bufTail = make([]byte, bufferLength)
+	of.bufLast = make([]byte, bufferLength)
 
 	if _, err := f.Seek(-bufferLength, io.SeekEnd); err != nil {
 		return nil, err
@@ -57,11 +57,11 @@ func NewOggFile(path string) (*OggFile, error) {
 			return nil, err
 		}
 
-		if _, err := f.Read(of.bufTail); err != nil {
+		if _, err := f.Read(of.bufLast); err != nil {
 			return nil, err
 		}
 
-		if bytes.Contains(of.bufTail, []byte(OggS)) {
+		if bytes.Contains(of.bufLast, []byte(OggS)) {
 			break
 		}
 	}
@@ -94,9 +94,9 @@ func (of *OggFile) GetDuration() time.Duration {
 	rate := int32(rateBytes[0]) + int32(rateBytes[1])<<8 +
 		int32(rateBytes[2])<<16 + int32(rateBytes[3])<<24
 
-	granuleIdx := bytes.LastIndex(of.bufTail, []byte(OggS)) +
+	granuleIdx := bytes.LastIndex(of.bufLast, []byte(OggS)) +
 		OggSLen + 2
-	granuleBytes := of.bufTail[granuleIdx : granuleIdx+8]
+	granuleBytes := of.bufLast[granuleIdx : granuleIdx+8]
 	granule := int64(granuleBytes[0]) + int64(granuleBytes[1])<<8 +
 		int64(granuleBytes[2])<<16 + int64(granuleBytes[3])<<24 +
 		int64(granuleBytes[4])<<32 + int64(granuleBytes[5])<<40 +