diff --git a/timm/models/davit.py b/timm/models/davit.py
index 32d48f73..639dec13 100644
--- a/timm/models/davit.py
+++ b/timm/models/davit.py
@@ -215,7 +215,7 @@ def window_reverse(windows : Tensor, window_size: int, H: int, W: int):
     Returns:
         x: (B, H, W, C)
     """
-    B = int(windows.size(dim=0) / (H * W / window_size / window_size))
+    B = int(windows.size(dim=0)[0] / (H * W / window_size / window_size))
     x = windows.view(B, H // window_size, W // window_size, window_size, window_size, -1)
     x = x.permute(0, 1, 3, 2, 4, 5).contiguous().view(B, H, W, -1)
     return x