diff --git a/aiocraft/mc/proto/play/clientbound/packet_multi_block_change.py b/aiocraft/mc/proto/play/clientbound/packet_multi_block_change.py
index 0ccbb92..033a6df 100644
--- a/aiocraft/mc/proto/play/clientbound/packet_multi_block_change.py
+++ b/aiocraft/mc/proto/play/clientbound/packet_multi_block_change.py
@@ -112,12 +112,12 @@ class PacketMultiBlockChange(Packet):
 		734 : [ ( 'chunkX', Int ), ( 'chunkZ', Int ), ( 'records', ArrayType(StructType(( 'horizontalPos', Byte ), ( 'y', Byte ), ( 'blockId', VarInt ), ), VarInt, ) ) ],
 		735 : [ ( 'chunkX', Int ), ( 'chunkZ', Int ), ( 'records', ArrayType(StructType(( 'horizontalPos', Byte ), ( 'y', Byte ), ( 'blockId', VarInt ), ), VarInt, ) ) ],
 		736 : [ ( 'chunkX', Int ), ( 'chunkZ', Int ), ( 'records', ArrayType(StructType(( 'horizontalPos', Byte ), ( 'y', Byte ), ( 'blockId', VarInt ), ), VarInt, ) ) ],
-		751 : [ ( 'chunkCoordinates', Int ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(TrailingData, VarInt, ) ) ],
-		755 : [ ( 'chunkCoordinates', Int ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(TrailingData, VarInt, ) ) ],
-		756 : [ ( 'chunkCoordinates', Int ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(TrailingData, VarInt, ) ) ],
-		757 : [ ( 'chunkCoordinates', Int ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(TrailingData, VarInt, ) ) ],
-		758 : [ ( 'chunkCoordinates', Int ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(TrailingData, VarInt, ) ) ],
-		759 : [ ( 'chunkCoordinates', Int ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(VarInt, VarInt, ) ) ],
-		760 : [ ( 'chunkCoordinates', Int ), ( 'suppressLightUpdates', Boolean ), ( 'records', ArrayType(VarInt, VarInt, ) ) ],
-		761 : [ ( 'chunkCoordinates', Int ), ( 'suppressLightUpdates', Boolean ), ( 'records', ArrayType(VarInt, VarInt, ) ) ]
+		751 : [ ( 'chunkCoordinates', Long ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(TrailingData, VarInt, ) ) ],
+		755 : [ ( 'chunkCoordinates', Long ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(TrailingData, VarInt, ) ) ],
+		756 : [ ( 'chunkCoordinates', Long ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(TrailingData, VarInt, ) ) ],
+		757 : [ ( 'chunkCoordinates', Long ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(TrailingData, VarInt, ) ) ],
+		758 : [ ( 'chunkCoordinates', Long ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(TrailingData, VarInt, ) ) ],
+		759 : [ ( 'chunkCoordinates', Long ), ( 'notTrustEdges', Boolean ), ( 'records', ArrayType(VarInt, VarInt, ) ) ],
+		760 : [ ( 'chunkCoordinates', Long ), ( 'suppressLightUpdates', Boolean ), ( 'records', ArrayType(VarInt, VarInt, ) ) ],
+		761 : [ ( 'chunkCoordinates', Long ), ( 'suppressLightUpdates', Boolean ), ( 'records', ArrayType(VarInt, VarInt, ) ) ]
 	}
diff --git a/compiler/proto.py b/compiler/proto.py
index a86e023..104a048 100644
--- a/compiler/proto.py
+++ b/compiler/proto.py
@@ -162,7 +162,13 @@ def mctype(slot_type:Any) -> Ref:
 				mctype(v["default"]) if "default" in v and v['default'] != 'void' else None,
 			)
 		elif t == "bitfield":
-			return Ref('Int') # TODO
+			# TODO can be made better...
+			size = 0
+			for field in v:
+				size += field["size"]
+			if size <= 32:
+				return Ref('Int')
+			return Ref('Long')
 		# elif t == "mapper": # ????
 		# 	return TrailingData
 		else: