diff --git a/SignalServiceKit/src/Messages/Attachments/TSAttachment.m b/SignalServiceKit/src/Messages/Attachments/TSAttachment.m
index f7774b960..fcbf930a8 100644
--- a/SignalServiceKit/src/Messages/Attachments/TSAttachment.m
+++ b/SignalServiceKit/src/Messages/Attachments/TSAttachment.m
@@ -16,6 +16,8 @@ NSUInteger const TSAttachmentSchemaVersion = 4;
 
 @property (nonatomic, nullable) NSString *sourceFilename;
 
+@property (nonatomic) NSString *contentType;
+
 @end
 
 @implementation TSAttachment