diff --git a/django_etesync/serializers.py b/django_etesync/serializers.py
index 6a495bf..5946293 100644
--- a/django_etesync/serializers.py
+++ b/django_etesync/serializers.py
@@ -60,6 +60,19 @@ class CollectionContentField(BinaryBase64Field):
         return None
 
 
+class ChunksField(serializers.RelatedField):
+    def to_representation(self, obj):
+        prefer_inline = self.context.get('prefer_inline', False)
+        if prefer_inline:
+            with open(obj.chunkFile.path, 'rb') as f:
+                return (obj.uid, b64encode(f.read()))
+        else:
+            return (obj.uid, )
+
+    def to_internal_value(self, data):
+        return (data[0], b64decode(data[1]))
+
+
 class CollectionItemChunkSerializer(serializers.ModelSerializer):
     class Meta:
         model = models.CollectionItemChunk
@@ -67,55 +80,15 @@ class CollectionItemChunkSerializer(serializers.ModelSerializer):
 
 
 class CollectionItemRevisionSerializer(serializers.ModelSerializer):
-    chunks = serializers.SlugRelatedField(
-        slug_field='uid',
+    chunks = ChunksField(
         queryset=models.CollectionItemChunk.objects.all(),
         many=True
     )
-    chunksUrls = serializers.SerializerMethodField('get_chunks_urls')
-    chunksData = serializers.SerializerMethodField('get_chunks_data')
     meta = BinaryBase64Field()
 
     class Meta:
         model = models.CollectionItemRevision
-        fields = ('chunks', 'meta', 'uid', 'deleted', 'chunksUrls', 'chunksData')
-
-    # FIXME: currently the user is exposed in the url. We don't want that, and we can probably avoid that but still
-    # save it under the user.
-    # We would probably be better off just let the user calculate the urls from the uid and a base url for the snapshot.
-    # E.g. chunkBaseUrl: "/media/bla/bla/" or chunkBaseUrl: "https://media.etesync.com/bla/bla"
-    def get_chunks_urls(self, obj):
-        prefer_inline = self.context.get('prefer_inline', False)
-        if prefer_inline:
-            return None
-
-        ret = []
-        for chunk in obj.chunks.all():
-            ret.append(chunk.chunkFile.url)
-
-        return ret
-
-    def get_chunks_data(self, obj):
-        prefer_inline = self.context.get('prefer_inline', False)
-        if not prefer_inline:
-            return None
-
-        ret = []
-        for chunk in obj.chunks.all():
-            with open(chunk.chunkFile.path, 'rb') as f:
-                ret.append(b64encode(f.read()))
-
-        return ret
-
-    def to_representation(self, instance):
-        ret = super().to_representation(instance)
-        prefer_inline = self.context.get('prefer_inline', False)
-        if prefer_inline:
-            ret.pop('chunksUrls')
-        else:
-            ret.pop('chunksData')
-
-        return ret
+        fields = ('chunks', 'meta', 'uid', 'deleted')
 
 
 class CollectionItemSerializer(serializers.ModelSerializer):