diff --git a/pybtc/connector/block_loader.py b/pybtc/connector/block_loader.py
index 5344b0b..1bef312 100644
--- a/pybtc/connector/block_loader.py
+++ b/pybtc/connector/block_loader.py
@@ -178,8 +178,8 @@ class BlockLoader:
                 for i in blocks:
                     self.parent.block_preload.set(i, blocks[i])
                 if blocks:
-                    last_tx = blocks[i]["tx"][len(blocks[i]["tx"]) - 1]
-                    pointer = (i << 42) + ((len(blocks[i]["tx"]) - 1) << 21) + (en(last_tx["vOut"]) - 1)
+                    last_tx = blocks[i]["rawTx"][len(blocks[i]["rawTx"]) - 1]
+                    pointer = (i << 42) + ((len(blocks[i]["rawTx"]) - 1) << 21) + (en(last_tx["vOut"]) - 1)
                     self.parent.checkpoints.append(pointer)