diff --git a/MVMCore/MVMCore/OtherHandlers/MVMCoreCache.h b/MVMCore/MVMCore/OtherHandlers/MVMCoreCache.h
index 6319fa5..5d2a48c 100644
--- a/MVMCore/MVMCore/OtherHandlers/MVMCoreCache.h
+++ b/MVMCore/MVMCore/OtherHandlers/MVMCoreCache.h
@@ -12,6 +12,9 @@
 #import <AVKit/AVKit.h>
 @class MVMCoreErrorObject;
 
+extern NSString * _Nonnull const KeyCachePolicy;
+extern NSString * _Nonnull const KeyCacheExpiry;
+
 //block returned when getting image
 //parameters are UIImage object for the image, NSData for gif images, UIImage object for the image, A BOOL to indicate if it is a fall back image.
 typedef void(^MVMCoreGetImageBlock)(UIImage * _Nullable, NSData * _Nullable, BOOL);
diff --git a/MVMCore/MVMCore/OtherHandlers/MVMCoreCache.m b/MVMCore/MVMCore/OtherHandlers/MVMCoreCache.m
index 3f1fa92..f2af3c3 100644
--- a/MVMCore/MVMCore/OtherHandlers/MVMCoreCache.m
+++ b/MVMCore/MVMCore/OtherHandlers/MVMCoreCache.m
@@ -17,6 +17,9 @@
 #import "MVMCoreErrorConstants.h"
 #import "MVMCoreLoggingHandlerHelper.h"
 
+NSString * _Nonnull const KeyCachePolicy = @"cachePolicy";
+NSString * _Nonnull const KeyCacheExpiry = @"expiry";
+
 @interface MVMCoreCache ()
 
 // The cache for json.
@@ -113,13 +116,13 @@ static NSString * const STATIC_CACHE_COMPONENT = @"StaticCache.txt";
 }
 
 - (nonnull NSDate *)getExpirationDateForJSON:(nonnull NSDictionary *)jsonDictionary {
-    NSDictionary *cachePolicy = [jsonDictionary dict:@"cachePolicy"];
-    NSTimeInterval interval = [[cachePolicy string:@"expiry"] doubleValue] / 1000;
+    NSDictionary *cachePolicy = [jsonDictionary dict:KeyCachePolicy];
+    NSTimeInterval interval = [[cachePolicy string:KeyCacheExpiry] doubleValue] / 1000;
     return [NSDate dateWithTimeIntervalSince1970:interval];
 }
 
 - (BOOL)shouldPersistentlyCacheJSON:(nonnull NSDictionary *)jsonDictionary {
-    NSDictionary *cachePolicy = [jsonDictionary dict:@"cachePolicy"];
+    NSDictionary *cachePolicy = [jsonDictionary dict:KeyCachePolicy];
     if (!cachePolicy || ![cachePolicy boolForKey:@"persist"]) {
         return NO;
     }