diff --git a/lib/common/certificate_test.go b/lib/common/certificate_test.go
index bfd02d9..b22827e 100644
--- a/lib/common/certificate_test.go
+++ b/lib/common/certificate_test.go
@@ -1,6 +1,8 @@
 package common
 
-import "testing"
+import (
+	"testing"
+)
 
 func TestCertificateTypeIsFirstByte(t *testing.T) {
 	bytes := []byte{0x03, 0x00, 0x00}
diff --git a/lib/common/date.go b/lib/common/date.go
index 07d0534..fddbac2 100644
--- a/lib/common/date.go
+++ b/lib/common/date.go
@@ -1,5 +1,11 @@
 package common
 
+/*
+I2P Date
+https://geti2p.net/en/docs/spec/common-structures#type_Date
+Accurate for version 0.9.24
+*/
+
 import (
 	"time"
 )
diff --git a/lib/common/date_test.go b/lib/common/date_test.go
index 3d3ef0e..7e0a8e0 100644
--- a/lib/common/date_test.go
+++ b/lib/common/date_test.go
@@ -1,6 +1,8 @@
 package common
 
-import "testing"
+import (
+	"testing"
+)
 
 func TestTimeFromMiliseconds(t *testing.T) {
 	next_day := Date{0x00, 0x00, 0x00, 0x00, 0x05, 0x26, 0x5c, 0x00}
diff --git a/lib/common/destination.go b/lib/common/destination.go
index 783e739..1c2bbca 100644
--- a/lib/common/destination.go
+++ b/lib/common/destination.go
@@ -1,5 +1,13 @@
 package common
 
+/*
+I2P Destination
+https://geti2p.net/en/docs/spec/common-structures#struct_Destination
+Accurate for version 0.9.24
+
+Identical to KeysAndCert
+*/
+
 import (
 	"github.com/bounce-chat/go-i2p/lib/common/base32"
 	"github.com/bounce-chat/go-i2p/lib/common/base64"
diff --git a/lib/common/integer.go b/lib/common/integer.go
index ed1c934..5d8e2df 100644
--- a/lib/common/integer.go
+++ b/lib/common/integer.go
@@ -1,5 +1,11 @@
 package common
 
+/*
+I2P Integer
+https://geti2p.net/en/docs/spec/common-structures#type_Integer
+Accurate for version 0.9.24
+*/
+
 import (
 	"encoding/binary"
 )
diff --git a/lib/common/key_certificate.go b/lib/common/key_certificate.go
index e1ca17a..aceb874 100644
--- a/lib/common/key_certificate.go
+++ b/lib/common/key_certificate.go
@@ -1,5 +1,11 @@
 package common
 
+/*
+I2P Key Certificate
+https://geti2p.net/en/docs/spec/common-structures#type_Certificate
+Accurate for version 0.9.24
+*/
+
 import (
 	"errors"
 	"github.com/bounce-chat/go-i2p/lib/crypto"
diff --git a/lib/common/lease.go b/lib/common/lease.go
index bfc62f2..38b9d1f 100644
--- a/lib/common/lease.go
+++ b/lib/common/lease.go
@@ -1,23 +1,67 @@
 package common
 
+/*
+I2P Lease
+https://geti2p.net/en/docs/spec/common-structures#struct_Lease
+Accurate for version 0.9.24
+
++----+----+----+----+----+----+----+----+
+| tunnel_gw                             |
++                                       +
+|                                       |
++                                       +
+|                                       |
++                                       +
+|                                       |
++----+----+----+----+----+----+----+----+
+|     tunnel_id     |      end_date
++----+----+----+----+----+----+----+----+
+                    |
++----+----+----+----+
+
+tunnel_gw :: Hash of the RouterIdentity of the tunnel gateway
+             length -> 32 bytes
+
+tunnel_id :: TunnelId
+             length -> 4 bytes
+
+end_date :: Date
+            length -> 8 bytes
+*/
+
 import (
 	"github.com/bounce-chat/go-i2p/lib/tunnel"
 )
 
-type Lease [44]byte
+const (
+	LEASE_SIZE           = 44
+	LEASE_HASH_SIZE      = 32
+	LEASE_TUNNEL_ID_SIZE = 4
+)
 
-func (lease Lease) TunnelGateway() (h Hash) {
-	copy(lease[:32], h[:])
+type Lease [LEASE_SIZE]byte
+
+//
+// Return the first 32 bytes of the Lease as a Hash.
+//
+func (lease Lease) TunnelGateway() (hash Hash) {
+	copy(hash[:], lease[:LEASE_HASH_SIZE])
 	return
 }
 
+//
+// Parse the TunnelID Integer in the Lease.
+//
 func (lease Lease) TunnelID() tunnel.TunnelID {
 	return tunnel.TunnelID(
-		Integer(lease[32:36]),
+		Integer(lease[LEASE_HASH_SIZE : LEASE_HASH_SIZE+LEASE_TUNNEL_ID_SIZE]),
 	)
 }
 
-func (lease Lease) Date() (d Date) {
-	copy(lease[36:], d[:])
+//
+// Return the Date inside the Lease.
+//
+func (lease Lease) Date() (date Date) {
+	copy(date[:], lease[LEASE_HASH_SIZE+LEASE_TUNNEL_ID_SIZE:])
 	return
 }
diff --git a/lib/common/string_test.go b/lib/common/string_test.go
index 90554f3..ae97b71 100644
--- a/lib/common/string_test.go
+++ b/lib/common/string_test.go
@@ -1,6 +1,8 @@
 package common
 
-import "testing"
+import (
+	"testing"
+)
 
 func TestStringReportsCorrectLength(t *testing.T) {
 	str_len, err := String([]byte{0x02, 0x00, 0x00}).Length()