diff --git a/src/ieee754.h b/src/ieee754.h
index 124d095..5cd36db 100644
--- a/src/ieee754.h
+++ b/src/ieee754.h
@@ -141,18 +141,14 @@
 
 
 
-
-#define IEEE754_UNION_IS_HALF   0
-#define IEEE754_UNION_IS_SINGLE 1
-#define IEEE754_UNION_IS_DOUBLE 2
+// Both tags the value and gives the size
+#define IEEE754_UNION_IS_HALF   2
+#define IEEE754_UNION_IS_SINGLE 4
+#define IEEE754_UNION_IS_DOUBLE 8
 
 typedef struct {
-    uint8_t uTag;  // One of IEEE754_IS_xxxx
-    union {
-        uint16_t u16;
-        uint32_t u32;
-        uint64_t u64;
-    };
+    uint8_t uSize;  // One of IEEE754_IS_xxxx
+    uint64_t uValue;
 } IEEE754_union;