diff --git a/src/sf_types.h b/src/sf_types.h
index f175c97..30f8b76 100644
--- a/src/sf_types.h
+++ b/src/sf_types.h
@@ -274,4 +274,9 @@ typedef struct sf_slice_size {
     int length;  //slice length
 } SFSliceSize;
 
+typedef struct sf_block_slice_key_info {
+    SFBlockKey block;
+    SFSliceSize slice;
+} SFBlockSliceKeyInfo;
+
 #endif