diff --git a/adafruit_ssd1325.py b/adafruit_ssd1325.py
index 23927f6..e6df5f0 100644
--- a/adafruit_ssd1325.py
+++ b/adafruit_ssd1325.py
@@ -63,7 +63,7 @@ class SSD1325(displayio.Display):
         (0, 90, 180, 270)
     """
 
-    def __init__(self, bus, **kwargs):
+    def __init__(self, bus: displayio.FourWire, **kwargs) -> None:
         # Patch the init sequence for 32 pixel high displays.
         init_sequence = bytearray(_INIT_SEQUENCE)
         height = kwargs["height"]