diff --git a/HISTORY.md b/HISTORY.md
index a0227196..1e4bf53e 100755
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -78,6 +78,9 @@
     * German
     * French
 
+### 2019-05-20
+* Objects, Blocks added plus- and minus- keys to key pressed predicate and hat block 
+
 ### 2019-05-16
 * Objects: more refactoring to generalize projection extensions
 
diff --git a/snap.html b/snap.html
index 686d73e1..417f9df1 100755
--- a/snap.html
+++ b/snap.html
@@ -6,9 +6,9 @@
         <link rel="shortcut icon" href="src/favicon.ico">
         <script type="text/javascript" src="src/morphic.js?version=2019-02-07"></script>
         <script type="text/javascript" src="src/widgets.js?version=2019-04-05"></script>
-        <script type="text/javascript" src="src/blocks.js?version=2019-05-08"></script>
+        <script type="text/javascript" src="src/blocks.js?version=2019-05-20"></script>
         <script type="text/javascript" src="src/threads.js?version=2019-05-15"></script>
-        <script type="text/javascript" src="src/objects.js?version=2019-05-16"></script>
+        <script type="text/javascript" src="src/objects.js?version=2019-05-20"></script>
         <script type="text/javascript" src="src/gui.js?version=2019-05-09"></script>
         <script type="text/javascript" src="src/paint.js?version=2019-02-22"></script>
         <script type="text/javascript" src="src/lists.js?version=2019-04-27"></script>
diff --git a/src/blocks.js b/src/blocks.js
index 131caf64..e75473fd 100644
--- a/src/blocks.js
+++ b/src/blocks.js
@@ -148,7 +148,7 @@ CustomCommandBlockMorph, SymbolMorph, ToggleButtonMorph, DialMorph*/
 
 // Global stuff ////////////////////////////////////////////////////////
 
-modules.blocks = '2019-May-08';
+modules.blocks = '2019-May-20';
 
 var SyntaxElementMorph;
 var BlockMorph;
@@ -1255,6 +1255,8 @@ SyntaxElementMorph.prototype.labelPart = function (spec) {
                     'right arrow': ['right arrow'],
                     'left arrow': ['left arrow'],
                     space : ['space'],
+                    '+' : ['+'],
+                    '-' : ['-'],
                     a : ['a'],
                     b : ['b'],
                     c : ['c'],
diff --git a/src/objects.js b/src/objects.js
index ff7b2110..e27724d4 100644
--- a/src/objects.js
+++ b/src/objects.js
@@ -84,7 +84,7 @@ BlockEditorMorph, BlockDialogMorph, PrototypeHatBlockMorph, localize,
 TableMorph, TableFrameMorph, normalizeCanvas, BooleanSlotMorph, HandleMorph,
 AlignmentMorph, Process, XML_Element, VectorPaintEditorMorph*/
 
-modules.objects = '2019-May-16';
+modules.objects = '2019-May-20';
 
 var SpriteMorph;
 var StageMorph;
@@ -7665,6 +7665,12 @@ StageMorph.prototype.processKeyEvent = function (event, action) {
     case 40:
         keyName = 'down arrow';
         break;
+    case 187:
+        keyName = '+';
+        break;
+    case 189:
+        keyName = '-';
+        break;
     default:
         keyName = String.fromCharCode(event.keyCode || event.charCode);
         if (event.ctrlKey || event.metaKey) {