diff --git a/docs/reference/plugins.rst b/docs/reference/plugins.rst
index 243d4f353f5..a34f813c1a1 100644
--- a/docs/reference/plugins.rst
+++ b/docs/reference/plugins.rst
@@ -276,6 +276,11 @@ Plugin reference
     :undoc-members:
     :show-inheritance:
 
+.. autoclass:: PIL.PsdImagePlugin._Layer()
+    :member-order: bysource
+    :members:
+    :show-inheritance:
+
 :mod:`~PIL.SgiImagePlugin` module
 ---------------------------------
 
diff --git a/src/PIL/PsdImagePlugin.py b/src/PIL/PsdImagePlugin.py
index e39843e9dc8..c33165980b7 100644
--- a/src/PIL/PsdImagePlugin.py
+++ b/src/PIL/PsdImagePlugin.py
@@ -21,6 +21,7 @@
 
 import io
 from functools import cached_property
+from typing import NamedTuple
 
 from . import Image, ImageFile, ImagePalette
 from ._binary import i8
@@ -48,6 +49,13 @@
 }
 
 
+class _Layer(NamedTuple):
+    name: str
+    mode: str
+    box: tuple[int, int, int, int]
+    tile: list[ImageFile._Tile]
+
+
 # --------------------------------------------------------------------.
 # read PSD images
 
@@ -150,9 +158,7 @@ def _open(self) -> None:
         self._min_frame = 1
 
     @cached_property
-    def layers(
-        self,
-    ) -> list[tuple[str, str, tuple[int, int, int, int], list[ImageFile._Tile]]]:
+    def layers(self) -> list[_Layer]:
         layers = []
         if self._layers_position is not None:
             if isinstance(self._fp, DeferredError):
@@ -192,9 +198,7 @@ def tell(self) -> int:
         return self.frame
 
 
-def _layerinfo(
-    fp: IO[bytes], ct_bytes: int
-) -> list[tuple[str, str, tuple[int, int, int, int], list[ImageFile._Tile]]]:
+def _layerinfo(fp: IO[bytes], ct_bytes: int) -> list[_Layer]:
     # read layerinfo block
     layers = []
 
@@ -280,7 +284,7 @@ def read(size: int) -> bytes:
             t = _maketile(fp, m, bbox, 1)
             if t:
                 tile.extend(t)
-        layerinfo.append((name, mode, bbox, tile))
+        layerinfo.append(_Layer(name, mode, bbox, tile))
 
     return layerinfo
 
@@ -306,7 +310,7 @@ def _maketile(
             if mode == "CMYK":
                 layer += ";I"
             tiles.append(ImageFile._Tile("raw", bbox, offset, layer))
-            offset = offset + xsize * ysize
+            offset += xsize * ysize
 
     elif compression == 1:
         #
@@ -320,7 +324,7 @@ def _maketile(
                 layer += ";I"
             tiles.append(ImageFile._Tile("packbits", bbox, offset, layer))
             for y in range(ysize):
-                offset = offset + i16(bytecount, i)
+                offset += i16(bytecount, i)
                 i += 2
 
     file.seek(offset)