diff --git a/SYCLStream.cpp b/SYCLStream.cpp
index 9e23175..76c0a8b 100644
--- a/SYCLStream.cpp
+++ b/SYCLStream.cpp
@@ -15,7 +15,7 @@ std::vector<sycl::device> devices;
 void getDeviceList(void);
 
 template <class T>
-SYCLStream<T>::SYCLStream(const int ARRAY_SIZE, const int device_index)
+SYCLStream<T>::SYCLStream(const size_t ARRAY_SIZE, const int device_index)
 : array_size {ARRAY_SIZE},
   d_a {ARRAY_SIZE},
   d_b {ARRAY_SIZE},
diff --git a/SYCLStream.h b/SYCLStream.h
index cd8e39a..e8b9134 100644
--- a/SYCLStream.h
+++ b/SYCLStream.h
@@ -21,7 +21,7 @@ class SYCLStream : public Stream<T>
 {
   protected:
     // Size of arrays
-    int array_size;
+    size_t array_size;
 
     // SYCL objects
     // Queue is a pointer because we allow device selection
@@ -35,7 +35,7 @@ class SYCLStream : public Stream<T>
 
   public:
 
-    SYCLStream(const int, const int);
+    SYCLStream(const size_t, const int);
     ~SYCLStream() = default;
 
     virtual void copy() override;