diff --git a/src/main/scad/puzzlecad/puzzlecad-burr.scad b/src/main/scad/puzzlecad/puzzlecad-burr.scad
index 992b8b5..a8b92ad 100644
--- a/src/main/scad/puzzlecad/puzzlecad-burr.scad
+++ b/src/main/scad/puzzlecad/puzzlecad-burr.scad
@@ -48,9 +48,11 @@ module burr_piece(burr_spec) {
  * The other arguments should be left as defaults (they're used for recursive calls to burr_plate).
  */
 
-module burr_plate(burr_specs, num_copies = 1) {
+module burr_plate(burr_specs, num_copies = 1, dup = []) {
     
-    burr_infos = [ for (burr_spec = burr_specs) to_burr_info(burr_spec) ];
+    burr_dups = dups(dup, burr_specs);
+    
+    burr_infos = [ for (burr_spec = burr_dups) to_burr_info(burr_spec) ];
     
     layout_burr_infos = $auto_layout ? auto_layout_plate(burr_infos) : burr_infos;
     
diff --git a/src/main/scad/puzzlecad/puzzlecad-parser.scad b/src/main/scad/puzzlecad/puzzlecad-parser.scad
index 2fd05e5..4ac4283 100644
--- a/src/main/scad/puzzlecad/puzzlecad-parser.scad
+++ b/src/main/scad/puzzlecad/puzzlecad-parser.scad
@@ -209,3 +209,7 @@ function bit_of(n, exponent) = floor(n / pow(2, exponent)) % 2;
 
 function copies(n, burr) = n == 0 ? [] : concat(copies(n-1, burr), [burr]);
     
+function dups(v, r, i = 0) =
+  i < len(v)
+    ? dups(v, concat(r, [for (x = [0:1:v[i][1] - 1]) r[v[i][0]]]), i + 1)
+    : r;