diff --git a/Packages/src/README.md b/Packages/src/README.md
index cfaae1a..71bff0d 100644
--- a/Packages/src/README.md
+++ b/Packages/src/README.md
@@ -1,4 +1,4 @@
-# Particle Effect For UGUI (UI Particle)
+#
Particle Effect For UGUI (UI Particle)
This package provides a component to render particle effects for uGUI in Unity 2018.2 or later.
The particle rendering is maskable and sortable, without the need for an extra Camera, RenderTexture, or Canvas.
@@ -117,6 +117,16 @@ Or, use [UpmGitExtension](https://github.com/mob-sakai/UpmGitExtension) to insta
+## ⚙ Upgrading from 3.x/4.x to 5.x
+
+### Breaking Changes
+
+- The default value of `UIParticle.scale` has been changed from `10` to `1`.
+- `UIParticle` no longer inherits from `MaskableGraphic`.
+-
+
+
+
## 🚀 Usage
### UIParticle Component
@@ -176,9 +186,10 @@ section.
### Script usage
```cs
-// Instant ParticleSystem prefab with UIParticle on runtime.
+// Instantiate ParticleSystem prefab with UIParticle on runtime.
var go = GameObject.Instantiate(prefab);
var uiParticle = go.AddComponent();
+uiParticle.scale = 100;
// Control by ParticleSystem.
particleSystem.Play();