diff --git a/slcan_attach.c b/slcan_attach.c
index df0dc98..e72610a 100644
--- a/slcan_attach.c
+++ b/slcan_attach.c
@@ -141,7 +141,7 @@ int main(int argc, char **argv)
 
 		case 'b':
 			btr = optarg;
-			if (strlen(btr) > 6)
+			if (strlen(btr) > 8)
 				print_usage(argv[0]);
 			break;
 
diff --git a/slcand.c b/slcand.c
index 4a15697..ac0c044 100644
--- a/slcand.c
+++ b/slcand.c
@@ -246,7 +246,7 @@ int main(int argc, char *argv[])
 			break;
 		case 'b':
 			btr = optarg;
-			if (strlen(btr) > 6)
+			if (strlen(btr) > 8)
 				print_usage(argv[0]);
 			break;
 		case 'F':