diff --git a/DESCRIPTION b/DESCRIPTION
index 1cc39c03..c1683377 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,7 +1,7 @@
 Package: spant
 Type: Package
 Title: MR Spectroscopy Analysis Tools
-Version: 2.20.0
+Version: 2.21.9000
 Date: 2024-05-01
 Authors@R: c(
     person("Martin", "Wilson", email = "martin@pipegrep.co.uk",
diff --git a/NEWS.md b/NEWS.md
index d8f649fc..aea1e610 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,3 +1,5 @@
+# spant 2.21.0
+
 # spant 2.20.0
 * Added vertical line colour and linetype options for stackplots.
 * Added option to give Y axis labels in units of seconds for spectrograms.
diff --git a/R/mrs_data_display.R b/R/mrs_data_display.R
index 4c994fdd..da12a095 100644
--- a/R/mrs_data_display.R
+++ b/R/mrs_data_display.R
@@ -410,9 +410,9 @@ image.mrs_data <- function(x, xlim = NULL, mode = "re", col = NULL,
     graphics::axis(2, at = y_ticks, labels = F, col = NA, col.ticks = "red")
   }
   
-  if (!is.null(vline)) graphics::abline(v = vline, col = "white")
+  if (!is.null(vline)) graphics::abline(v = vline, col = "white", lty = 2)
   
-  if (!is.null(hline)) graphics::abline(h = hline, col = "white")
+  if (!is.null(hline)) graphics::abline(h = hline, col = "white", lty = 2)
   
   if (restore_def_par) graphics::par(.pardefault)
 }