diff --git a/src/engine/monitor-record.js b/src/engine/monitor-record.js
index daa6f9db1..1259d5252 100644
--- a/src/engine/monitor-record.js
+++ b/src/engine/monitor-record.js
@@ -12,6 +12,7 @@ const MonitorRecord = Record({
     mode: 'default',
     sliderMin: 0,
     sliderMax: 100,
+    isDiscrete: true,
     x: null, // (x: null, y: null) Indicates that the monitor should be auto-positioned
     y: null,
     width: 0,
diff --git a/src/serialization/sb2.js b/src/serialization/sb2.js
index f8d1b9e65..2e5a556af 100644
--- a/src/serialization/sb2.js
+++ b/src/serialization/sb2.js
@@ -381,6 +381,7 @@ const parseMonitorObject = (object, runtime, targets, extensions) => {
         mode: object.mode,
         sliderMin: object.sliderMin,
         sliderMax: object.sliderMax,
+        isDiscrete: object.isDiscrete,
         x: object.x,
         y: object.y,
         width: object.width,
diff --git a/src/serialization/sb3.js b/src/serialization/sb3.js
index 5b4d5a76e..6aa592c73 100644
--- a/src/serialization/sb3.js
+++ b/src/serialization/sb3.js
@@ -506,6 +506,7 @@ const serializeMonitors = function (monitors) {
         if (monitorData.mode !== 'list') {
             serializedMonitor.sliderMin = monitorData.sliderMin;
             serializedMonitor.sliderMax = monitorData.sliderMax;
+            serializedMonitor.isDiscrete = monitorData.isDiscrete;
         }
         return serializedMonitor;
     });
diff --git a/test/fixtures/monitors.sb2 b/test/fixtures/monitors.sb2
index 2b9ede376..587488905 100644
Binary files a/test/fixtures/monitors.sb2 and b/test/fixtures/monitors.sb2 differ
diff --git a/test/integration/monitors_sb2.js b/test/integration/monitors_sb2.js
index a2c263487..12ab92a83 100644
--- a/test/integration/monitors_sb2.js
+++ b/test/integration/monitors_sb2.js
@@ -37,6 +37,7 @@ test('importing sb2 project with monitors', t => {
         t.equal(monitorRecord.mode, 'slider');
         t.equal(monitorRecord.sliderMin, -200); // Make sure these are imported for sliders.
         t.equal(monitorRecord.sliderMax, 30);
+        t.equal(monitorRecord.isDiscrete, false);
         t.equal(monitorRecord.x, 5); // These are imported for all monitors, just check once.
         t.equal(monitorRecord.y, 59);
         t.equal(monitorRecord.visible, true);
@@ -61,8 +62,8 @@ test('importing sb2 project with monitors', t => {
         t.equal(monitorRecord.opcode, 'data_listcontents');
         t.equal(monitorRecord.mode, 'list');
         t.equal(monitorRecord.visible, true);
-        t.equal(monitorRecord.width, 104); // Make sure these are imported from lists.
-        t.equal(monitorRecord.height, 204);
+        t.equal(monitorRecord.width, 106); // Make sure these are imported from lists.
+        t.equal(monitorRecord.height, 206);
 
         // Backdrop name monitor is visible, not sprite specific
         // should get imported with id that references the name parameter
diff --git a/test/integration/monitors_sb2_to_sb3.js b/test/integration/monitors_sb2_to_sb3.js
index 4fb26bbf8..ec881c2d3 100644
--- a/test/integration/monitors_sb2_to_sb3.js
+++ b/test/integration/monitors_sb2_to_sb3.js
@@ -54,6 +54,7 @@ test('saving and loading sb2 project with monitors preserves sliderMin and slide
         t.equal(monitorRecord.mode, 'slider');
         t.equal(monitorRecord.sliderMin, -200); // Make sure these are imported for sliders.
         t.equal(monitorRecord.sliderMax, 30);
+        t.equal(monitorRecord.isDiscrete, false);
         t.equal(monitorRecord.x, 5); // These are imported for all monitors, just check once.
         t.equal(monitorRecord.y, 59);
         t.equal(monitorRecord.visible, true);
@@ -78,8 +79,8 @@ test('saving and loading sb2 project with monitors preserves sliderMin and slide
         t.equal(monitorRecord.opcode, 'data_listcontents');
         t.equal(monitorRecord.mode, 'list');
         t.equal(monitorRecord.visible, true);
-        t.equal(monitorRecord.width, 104); // Make sure these are imported from lists.
-        t.equal(monitorRecord.height, 204);
+        t.equal(monitorRecord.width, 106); // Make sure these are imported from lists.
+        t.equal(monitorRecord.height, 206);
 
         // Backdrop name monitor is visible, not sprite specific
         // should get imported with id that references the name parameter
diff --git a/test/integration/monitors_sb3.js b/test/integration/monitors_sb3.js
index 3c5c08f9e..f55edb864 100644
--- a/test/integration/monitors_sb3.js
+++ b/test/integration/monitors_sb3.js
@@ -39,10 +39,9 @@ test('importing sb3 project with monitors', t => {
         t.equal(monitorRecord.opcode, 'data_variable');
         t.equal(monitorRecord.mode, 'default');
         // The following few properties are imported for all monitors, just check once.
-        // sliderMin and sliderMax are currently not implemented,
-        // but should still get default values serialized and deserialized correctly
         t.equal(monitorRecord.sliderMin, 0);
         t.equal(monitorRecord.sliderMax, 100);
+        t.equal(monitorRecord.isDiscrete, true); // The default if not present
         t.equal(monitorRecord.x, 10);
         t.equal(monitorRecord.y, 62);
         // Height and width are only used for list monitors and should default to 0