diff --git a/docs/assets/img/product_pics/unit/4_relay/4relay.webp b/docs/assets/img/product_pics/unit/4_relay/4relay.webp
new file mode 100644
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diff --git a/docs/zh_CN/README.md b/docs/zh_CN/README.md
index 775f192c..ff2bf3ae 100644
--- a/docs/zh_CN/README.md
+++ b/docs/zh_CN/README.md
@@ -123,8 +123,8 @@
 
     const unit_list = [
       //Sensor class
-      {a:"/#/zh_CN/unit/mic", img:"https://m5stack.oss-cn-shenzhen.aliyuncs.com/image/m5-docs_homepage/unit/ultrasonic.webp", p:"Ultrasonic", sku:"U098" ,kw:"ULTRASONIC DISTANCE SENSOR"},
-      {a:"/#/zh_CN/unit/mic", img:"https://m5stack.oss-cn-shenzhen.aliyuncs.com/image/m5-docs_homepage/unit/mic.webp", p:"Microphone", sku:"U096" ,kw:"MIC SOUND SENSOR", category:"Sensor class"},
+      {a:"/#/zh_CN/unit/mic", img:"https://m5stack.oss-cn-shenzhen.aliyuncs.com/image/m5-docs_homepage/unit/ultrasonic.webp", p:"Ultrasonic", sku:"U098" ,kw:"ULTRASONIC DISTANCE SENSOR" , category:"Sensor class"},
+      {a:"/#/zh_CN/unit/mic", img:"https://m5stack.oss-cn-shenzhen.aliyuncs.com/image/m5-docs_homepage/unit/mic.webp", p:"Microphone", sku:"U096" ,kw:"MIC SOUND SENSOR"},
       {a:"/#/zh_CN/unit/ameter", img:"https://m5stack.oss-cn-shenzhen.aliyuncs.com/image/m5-docs_homepage/unit/ameter.webp", p:"Ammeter", sku:"U086" ,kw:"AMETER SENSOR"},
       {a:"/#/zh_CN/unit/vmeter", img:"https://m5stack.oss-cn-shenzhen.aliyuncs.com/image/m5-docs_homepage/unit/vmeter.webp", p:"Voltmeter", sku:"U087" ,kw:" VMETER  VOLT SENSOR"},
       {a:"/#/zh_CN/unit/earth", img:"https://static-cdn.m5stack.com/image/m5-docs_homepage/unit/unit_earth_01.webp", p:"EARTH", sku:"U019" ,kw:"EARTH SENSOR"},