diff --git a/disassem.pl b/disassem.pl
index 42b028b..fa1d884 100755
--- a/disassem.pl
+++ b/disassem.pl
@@ -210,7 +210,7 @@ for my $pass (0..1) {
 open LABELS, ">input.labels" or die $!;
 
 foreach my $addr (sort keys %labels) {
-    printf LABELS "%s: %.6x\n", $labels{$addr}, $addr
+    printf LABELS "%s: %06x\n", $labels{$addr}, $addr
 	if defined($labels{$addr});
 }