diff --git a/xvf3800.py b/xvf3800.py
index 9f4ce99..7ad0d52 100644
--- a/xvf3800.py
+++ b/xvf3800.py
@@ -96,7 +96,7 @@ class XVF3800:
     # --- LEDs ---
 
     def led_off(self):
-        self._write(GPO_RESID, LED_EFFECT_CMD, struct.pack("<I", 0))
+        self._write(GPO_RESID, LED_EFFECT_CMD, bytes([0]))
 
     @staticmethod
     def _color_bytes(color: int) -> bytes:
@@ -109,23 +109,23 @@ class XVF3800:
     def led_solid(self, color: int):
         """Solid color on all LEDs. color is 0xRRGGBB."""
         self._write(GPO_RESID, LED_COLOR_CMD, self._color_bytes(color))
-        self._write(GPO_RESID, LED_EFFECT_CMD, struct.pack("<I", 3))
+        self._write(GPO_RESID, LED_EFFECT_CMD, bytes([3]))
 
     def led_breath(self, color: int, brightness: int = 128):
         """Breathing effect."""
         self._write(GPO_RESID, LED_COLOR_CMD, self._color_bytes(color))
-        self._write(GPO_RESID, LED_BRIGHTNESS_CMD, struct.pack("<I", brightness))
-        self._write(GPO_RESID, LED_EFFECT_CMD, struct.pack("<I", 1))
+        self._write(GPO_RESID, LED_BRIGHTNESS_CMD, bytes([brightness]))
+        self._write(GPO_RESID, LED_EFFECT_CMD, bytes([1]))
 
     def led_doa(self, base_color: int = 0x003333, doa_color: int = 0x00FFFF):
         """DoA indicator mode — shows beam direction on LED ring."""
         data = self._color_bytes(base_color) + self._color_bytes(doa_color)
         self._write(GPO_RESID, LED_DOA_COLOR_CMD, data)
-        self._write(GPO_RESID, LED_EFFECT_CMD, struct.pack("<I", 4))
+        self._write(GPO_RESID, LED_EFFECT_CMD, bytes([4]))
 
     def led_rainbow(self, brightness: int = 128):
-        self._write(GPO_RESID, LED_BRIGHTNESS_CMD, struct.pack("<I", brightness))
-        self._write(GPO_RESID, LED_EFFECT_CMD, struct.pack("<I", 2))
+        self._write(GPO_RESID, LED_BRIGHTNESS_CMD, bytes([brightness]))
+        self._write(GPO_RESID, LED_EFFECT_CMD, bytes([2]))
 
 
 class XVF3800Manager: