diff --git a/YYModel/NSObject+YYModel.h b/YYModel/NSObject+YYModel.h
index 73f62ec..de8a399 100644
--- a/YYModel/NSObject+YYModel.h
+++ b/YYModel/NSObject+YYModel.h
@@ -321,9 +321,9 @@ NS_ASSUME_NONNULL_BEGIN
  
         @interface YYAttributes
         @property NSString *name;
-        @property NSArray *shadows;
-        @property NSSet *borders;
-        @property NSDictionary *attachments;
+        @property NSArray <YYShadow *> *shadows;
+        @property NSSet <YYBorder *> *borders;
+        @property NSDictionary <NSString *, YYAttachment *> *attachments;
         @end
  
         @implementation YYAttributes
diff --git a/YYModel/NSObject+YYModel.m b/YYModel/NSObject+YYModel.m
index 3d7c470..38ee1b7 100644
--- a/YYModel/NSObject+YYModel.m
+++ b/YYModel/NSObject+YYModel.m
@@ -1205,6 +1205,7 @@ static id ModelToJSONObjectRecursive(NSObject *model) {
     if ([model isKindOfClass:[NSAttributedString class]]) return ((NSAttributedString *)model).string;
     if ([model isKindOfClass:[NSDate class]]) return [YYISODateFormatter() stringFromDate:(id)model];
     if ([model isKindOfClass:[NSData class]]) return nil;
+    if ([model isKindOfClass:[NSValue class]]) return model;
     
     
     _YYModelMeta *modelMeta = [_YYModelMeta metaWithClass:[model class]];