diff --git a/queue.py b/queue.py
index d3e8a8a..3a83715 100644
--- a/queue.py
+++ b/queue.py
@@ -70,9 +70,10 @@ seg_map = {
 @click.option('-b', '--baudrate', type=int, default=9600)
 @click.option('-w', '--display-width', type=int, default=32)
 @click.option('-i', '--message-interval', type=float, default=30)
+@click.option('-g', '--global-brightness', type=click.IntRange(0, 15), default=15)
 @click.argument('database')
 @click.argument('port')
-def cli(database, port, baudrate, message_interval, display_width):
+def cli(database, port, baudrate, message_interval, display_width, global_brightness):
     db = sqlite3.connect(database)
     ser = serial.Serial(port, baudrate)
 
@@ -120,7 +121,7 @@ def cli(database, port, baudrate, message_interval, display_width):
 
                 line = line.center(display_width)[:display_width]
                 line_mapped = [seg_map.get(c, seg_map['#']) for c in line]
-                formatted = ''.join(f'{d:02x}' for d in line_mapped) + '\n'
+                formatted = ''.join(f'{global_brightness:1x}{d:02x}' for d in line_mapped) + '\n'
                 time.sleep(interval)
                 ser.write(formatted)
                 ser.flush()