diff --git a/AsyncDisplayKit/Layout/ASAsciiArtBoxCreator.h b/AsyncDisplayKit/Layout/ASAsciiArtBoxCreator.h
index 3be6ed88de..198e792d1e 100644
--- a/AsyncDisplayKit/Layout/ASAsciiArtBoxCreator.h
+++ b/AsyncDisplayKit/Layout/ASAsciiArtBoxCreator.h
@@ -41,7 +41,7 @@
  *  |  ASTextNode  ASTextNode  ASTextNode  |
  *  ----------------------------------------
  */
-+ (NSString *)horizontalBoxStringForChildren:(NSArray<NSString *> *)children parent:(NSString *)parent;
++ (NSString *)horizontalBoxStringForChildren:(NSArray *)children parent:(NSString *)parent;
 
 /**
  *  Renders an ascii art box with the children aligned vertically.
@@ -52,7 +52,7 @@
  *   |     ASTextNode    |
  *   ---------------------
  */
-+ (NSString *)verticalBoxStringForChildren:(NSArray<NSString *> *)children parent:(NSString *)parent;
++ (NSString *)verticalBoxStringForChildren:(NSArray *)children parent:(NSString *)parent;
 
 @end
 
diff --git a/AsyncDisplayKit/Layout/ASAsciiArtBoxCreator.m b/AsyncDisplayKit/Layout/ASAsciiArtBoxCreator.m
index 9ec7e213bf..ea9ef9490c 100644
--- a/AsyncDisplayKit/Layout/ASAsciiArtBoxCreator.m
+++ b/AsyncDisplayKit/Layout/ASAsciiArtBoxCreator.m
@@ -53,13 +53,13 @@ typedef NS_ENUM(NSUInteger, PIDebugBoxPaddingLocation)
 
 @implementation ASAsciiArtBoxCreator
 
-+ (NSString *)horizontalBoxStringForChildren:(NSArray<NSString *> *)children parent:(NSString *)parent
++ (NSString *)horizontalBoxStringForChildren:(NSArray *)children parent:(NSString *)parent
 {
   if ([children count] == 0) {
     return parent;
   }
   
-  NSMutableArray<NSArray<NSString *> *> *childrenLines = [NSMutableArray array];
+  NSMutableArray *childrenLines = [NSMutableArray array];
   
   // split the children into lines
   NSUInteger lineCountPerChild = 0;
@@ -83,12 +83,12 @@ typedef NS_ENUM(NSUInteger, PIDebugBoxPaddingLocation)
     [childrenLines addObject:lines];
   }
   
-  NSMutableArray<NSString *> *concatenatedLines = [NSMutableArray array];
+  NSMutableArray *concatenatedLines = [NSMutableArray array];
   NSString *padding = [NSString debugbox_stringWithString:@" " repeatedCount:kDebugBoxPadding];
   for (NSUInteger index = 0; index < lineCountPerChild; index++) {
     NSMutableString *line = [[NSMutableString alloc] init];
     [line appendFormat:@"|%@",padding];
-    for (NSArray<NSString *> *childLines in childrenLines) {
+    for (NSArray *childLines in childrenLines) {
       [line appendFormat:@"%@%@", childLines[index], padding];
     }
     [line appendString:@"|"];
@@ -119,13 +119,13 @@ typedef NS_ENUM(NSUInteger, PIDebugBoxPaddingLocation)
   
 }
 
-+ (NSString *)verticalBoxStringForChildren:(NSArray<NSString *> *)children parent:(NSString *)parent
++ (NSString *)verticalBoxStringForChildren:(NSArray *)children parent:(NSString *)parent
 {
   if ([children count] == 0) {
     return parent;
   }
   
-  NSMutableArray<NSString *> *childrenLines = [NSMutableArray array];
+  NSMutableArray *childrenLines = [NSMutableArray array];
   
   NSUInteger maxChildLength = 0;
   for (NSString *child in children) {
@@ -167,7 +167,7 @@ typedef NS_ENUM(NSUInteger, PIDebugBoxPaddingLocation)
   return [childrenLines componentsJoinedByString:@"\n"];
 }
 
-+ (NSMutableArray *)appendTopAndBottomToBoxString:(NSMutableArray<NSString *> *)boxStrings parent:(NSString *)parent
++ (NSMutableArray *)appendTopAndBottomToBoxString:(NSMutableArray *)boxStrings parent:(NSString *)parent
 {
   NSUInteger totalLineLength = [boxStrings[0] length];
   [boxStrings addObject:[NSString debugbox_stringWithString:@"-" repeatedCount:totalLineLength]];
diff --git a/AsyncDisplayKit/Layout/ASLayoutSpec.h b/AsyncDisplayKit/Layout/ASLayoutSpec.h
index cd177ce891..6426317b91 100644
--- a/AsyncDisplayKit/Layout/ASLayoutSpec.h
+++ b/AsyncDisplayKit/Layout/ASLayoutSpec.h
@@ -101,7 +101,7 @@
 /**
  *  Used by other layout specs to create ascii art debug strings
  */
-+ (NSString *)asciiArtStringForChildren:(NSArray<id<ASLayoutableAsciiArtProtocol>> *)children parentName:(NSString *)parentName direction:(ASStackLayoutDirection)direction;
-+ (NSString *)asciiArtStringForChildren:(NSArray<id<ASLayoutableAsciiArtProtocol>> *)children parentName:(NSString *)parentName;
++ (NSString *)asciiArtStringForChildren:(NSArray *)children parentName:(NSString *)parentName direction:(ASStackLayoutDirection)direction;
++ (NSString *)asciiArtStringForChildren:(NSArray *)children parentName:(NSString *)parentName;
 
 @end
diff --git a/AsyncDisplayKit/Layout/ASLayoutSpec.mm b/AsyncDisplayKit/Layout/ASLayoutSpec.mm
index f14fdca6cc..35beca3161 100644
--- a/AsyncDisplayKit/Layout/ASLayoutSpec.mm
+++ b/AsyncDisplayKit/Layout/ASLayoutSpec.mm
@@ -128,7 +128,7 @@ static NSString * const kDefaultChildrenKey = @"kDefaultChildrenKey";
 
 #pragma mark - ASLayoutableAsciiArtProtocol
 
-+ (NSString *)asciiArtStringForChildren:(NSArray<id<ASLayoutableAsciiArtProtocol>> *)children parentName:(NSString *)parentName direction:(ASStackLayoutDirection)direction
++ (NSString *)asciiArtStringForChildren:(NSArray *)children parentName:(NSString *)parentName direction:(ASStackLayoutDirection)direction
 {
   NSMutableArray *childStrings = [NSMutableArray array];
   for (id<ASLayoutableAsciiArtProtocol> layoutChild in children) {
@@ -143,7 +143,7 @@ static NSString * const kDefaultChildrenKey = @"kDefaultChildrenKey";
   return [ASAsciiArtBoxCreator verticalBoxStringForChildren:childStrings parent:parentName];
 }
 
-+ (NSString *)asciiArtStringForChildren:(NSArray<id<ASLayoutableAsciiArtProtocol>> *)children parentName:(NSString *)parentName
++ (NSString *)asciiArtStringForChildren:(NSArray *)children parentName:(NSString *)parentName
 {
   return [self asciiArtStringForChildren:children parentName:parentName direction:ASStackLayoutDirectionHorizontal];
 }