diff --git a/README.md b/README.md
index d3565bb..0a373b2 100644
--- a/README.md
+++ b/README.md
@@ -12,6 +12,10 @@ To be decided, but at this moment this code is open source and free to use for n
 
 ## Changelog
 
+### 0.2.1
+* Fixed input property constraints on elements
+* Added NOT gate
+
 ### 0.2.0
 * Switched to a dark theme
 * Added left hand toolbar
diff --git a/index.html b/index.html
index 057b4fe..b023c58 100644
--- a/index.html
+++ b/index.html
@@ -36,6 +36,7 @@
     <input type="button" id="btn_AddNOR" value="!| NOR"/><br />
     <input type="button" id="btn_AddXOR" value="^ XOR"/><br />
     <input type="button" id="btn_AddXNOR" value="!^ XNOR"/><br />
+    <input type="button" id="btn_AddNOT" value="! NOT"/><br />
     <input type="button" id="btn_AddSWITCH" value="|- SWITCH"/><br />
     <input type="button" id="btn_AddCLK" value="🕑 Clock"/><br />
     <input type="button" id="btn_Delete" value="🗑 Delete"/>
diff --git a/js/logicengine.js b/js/logicengine.js
index 67aae09..9d87f9b 100644
--- a/js/logicengine.js
+++ b/js/logicengine.js
@@ -205,7 +205,7 @@ class Element extends CanvasTools {
     this.Properties = new Array();
     this.LogicEngine = logicengine;
 
-    let inputProperty = new ElementProperty("Inputs","int",{CBObject: this,CBFunction: "ChangeInputs"},2,Inputs);
+    let inputProperty = new ElementProperty("Inputs","int",{CBObject: this,CBFunction: "ChangeInputs"},2,Inputs,false,2);
     this.Properties.push(inputProperty);
   }
 
@@ -454,6 +454,7 @@ class inputElement extends Element {
     this.Name = "InputElement";
     this.Output = false;
     this.Width = 100;
+    this.removeProperty("Inputs");
   }
 
   getOutput() {
@@ -579,6 +580,7 @@ class LogicXOR extends Element {
   constructor(logicengine) {
     super(logicengine,2); // Only 2 inputs on XOR
     this.Name = "XOR";
+    this.removeProperty("Inputs");
   }
 
   getOutput() {
@@ -602,6 +604,7 @@ class LogicXNOR extends Element {
   constructor(logicengine) {
     super(logicengine,2); // Only 2 inputs on XOR
     this.Name = "XNOR";
+    this.removeProperty("Inputs");
   }
 
   getOutput() {
@@ -621,6 +624,29 @@ class LogicXNOR extends Element {
   }
 }
 
+class LogicNOT extends Element {
+  constructor(logicengine) {
+    super(logicengine,1); // Only 1 inputs on NOT
+    this.Name = "NOT";
+    this.removeProperty("Inputs");
+  }
+
+  getOutput() {
+    if (this.Inputs[0]) return false;
+    return true;
+  }
+
+  drawElement(x,y,ctx) {
+    let drawWidth = this.Width;
+    let drawHeight = this.Height;
+
+    this.drawBorderBox(ctx, x,y,drawWidth,drawHeight);
+    this.drawTextCentered(ctx,x,y,drawWidth,drawHeight,"|>🞄");
+    this.drawInputs(ctx,x,y);
+    this.drawOutputs(ctx,x,y);
+  }
+}
+
 
 class elementContainer {
   constructor() {
diff --git a/js/main.js b/js/main.js
index 32b801d..3b545ca 100644
--- a/js/main.js
+++ b/js/main.js
@@ -2,7 +2,7 @@
     MatCat BrowserLogic Simulator
  */
 
-let Version = "0.2.0";
+let Version = "0.2.1";
 let spanVersion = document.getElementById("version");
 spanVersion.innerText = Version;
 // get the canvas and get the engine object going
@@ -91,6 +91,13 @@ btn_AddXNOR.addEventListener('click', function(evt) {
   logicEngine.ActiveContainer.AddElement(newXNOR);
 }, false);
 
+btn_AddNOT.addEventListener('click', function(evt) {
+  let newNOT = new LogicNOT(logicEngine);
+  newNOT.X = 20;
+  newNOT.Y = 20;
+  logicEngine.ActiveContainer.AddElement(newNOT);
+}, false);
+
 let btn_AddSWITCH = document.getElementById("btn_AddSWITCH");
 btn_AddSWITCH.addEventListener('click', function(evt) {
   let newSWITCH = new InputSwitch(logicEngine);