diff --git a/sql/gamedb.sql b/sql/gamedb.sql
index 86acefb5..5054e1a7 100644
--- a/sql/gamedb.sql
+++ b/sql/gamedb.sql
@@ -126,7 +126,7 @@ CREATE TABLE `t_bag` (
   `createtime` int(11) NOT NULL DEFAULT '0' COMMENT '创建时间',
   `modifytime` int(11) NOT NULL DEFAULT '0' COMMENT '修改时间',
   PRIMARY KEY (`idx`),
-  UNIQUE KEY `item_uuid` (`account_id`, `item_id`),
+  KEY `item_id` (`item_id`),
   KEY `account_id` (`account_id`)
 ) ENGINE=InnoDB AUTO_INCREMENT=10001 DEFAULT CHARSET=utf8 COLLATE=utf8_bin;
 /*!40101 SET character_set_client = @saved_cs_client */;
diff --git a/webapp/models/Bag.php b/webapp/models/Bag.php
index bb5de328..1a5cf24c 100644
--- a/webapp/models/Bag.php
+++ b/webapp/models/Bag.php
@@ -3,6 +3,7 @@
 namespace models;
 
 require_once('mt/Item.php');
+require_once('mt/ChipQuality.php');
 
 use mt;
 use phpcommon\SqlHelper;
@@ -44,8 +45,10 @@ class Bag extends BaseModel {
     public static function toDto($row)
     {
         return array(
+            'item_uniid' => $row['idx'],
             'item_id' => $row['item_id'],
             'item_num' => $row['item_num'],
+            'attr' => emptyReplace(json_decode($row['rand_attr'], true), array()),
         );
     }
 
@@ -78,29 +81,54 @@ class Bag extends BaseModel {
         if (myself()->_isVirtualItem($itemId)) {
             return;
         }
+        if ($itemNum <= 0) {
+            return;
+        }
         $itemMeta = mt\Item::get($itemId);
         if (!$itemMeta) {
             return;
         }
-        SqlHelper::upsert
-            (myself()->_getSelfMysql(),
-             't_bag',
-             array(
-                 'account_id' => myself()->_getAccountId(),
-                 'item_id' => $itemId
-             ),
-             array(
-                 'item_num' => function () use($itemNum) { return "item_num + {$itemNum}";},
-                 'modifytime' => myself()->_getNowTime(),
-             ),
-             array(
-                 'account_id' => myself()->_getAccountId(),
-                 'item_id' => $itemId,
-                 'item_num' => $itemNum,
-                 'createtime' => myself()->_getNowTime(),
-                 'modifytime' => myself()->_getNowTime()
-             )
-            );
+        if ($itemMeta['cannot_stack']) {
+            $randAttr = array();
+            if (mt\Item::isRandAttrItem($itemMeta)) {
+                $qualityMeta = mt\ChipQuality::getByQuality($itemMeta['quality']);
+                if ($qualityMeta) {
+                    $randAttr = mt\ChipQuality::getRandAttr($qualityMeta);
+                }
+            }
+            SqlHelper::insert
+                (myself()->_getSelfMysql(),
+                 't_bag',
+                 array(
+                     'account_id' => myself()->_getAccountId(),
+                     'item_id' => $itemId,
+                     'item_num' => 1,
+                     'rand_attr' => json_encode($randAttr),
+                     'createtime' => myself()->_getNowTime(),
+                     'modifytime' => myself()->_getNowTime()
+                 )
+                );
+        } else {
+            SqlHelper::upsert
+                (myself()->_getSelfMysql(),
+                 't_bag',
+                 array(
+                     'account_id' => myself()->_getAccountId(),
+                     'item_id' => $itemId
+                 ),
+                 array(
+                     'item_num' => function () use($itemNum) { return "item_num + {$itemNum}";},
+                     'modifytime' => myself()->_getNowTime(),
+                 ),
+                 array(
+                     'account_id' => myself()->_getAccountId(),
+                     'item_id' => $itemId,
+                     'item_num' => $itemNum,
+                     'createtime' => myself()->_getNowTime(),
+                     'modifytime' => myself()->_getNowTime()
+                 )
+                );
+        }
     }
 
     public static function decItem($itemId, $itemNum)
diff --git a/webapp/mt/ChipQuality.php b/webapp/mt/ChipQuality.php
new file mode 100644
index 00000000..bef844b8
--- /dev/null
+++ b/webapp/mt/ChipQuality.php
@@ -0,0 +1,66 @@
+<?php
+
+namespace mt;
+
+require_once('mt/AttrHelper.php');
+require_once('mt/StrHelper.php');
+
+use phpcommon;
+
+class ChipQuality {
+
+    public static function get($id)
+    {
+        return getXVal(self::getMetaList(), $id);
+    }
+
+    public static function getByQuality($quality)
+    {
+        self::mustBeQualityHash();
+        return getXVal(self::$qualityHash, $quality, null);
+    }
+
+    public static function getRandAttr($qualityMeta)
+    {
+        $nums = explode(':', $qualityMeta['rand_attrs_num']);
+        $attrs = StrHelper::parseList($qualityMeta['rand_attrs'], array('|', ':'));
+        $num = rand($nums[0], $nums[1]);
+        shuffle($attrs);
+        $result = array();
+        $i = 0;
+        foreach ($attrs as $item) {
+            if ($i < $num) {
+                array_push($result,
+                           array(
+                               'attr_id' => $item[0],
+                               'type' => $item[1],
+                               'val' => rand($item[2], $item[3])
+                           ));
+            }
+            ++$i;
+        }
+        return $result;
+    }
+
+    protected static function getMetaList()
+    {
+        if (!self::$metaList) {
+            self::$metaList = getMetaTable('chipQuality@chipQuality.php');
+        }
+        return self::$metaList;
+    }
+
+    protected static function mustBeQualityHash()
+    {
+        if (!self::$qualityHash) {
+            self::$qualityHash = array();
+            foreach (self::getMetaList() as $meta) {
+                self::$qualityHash[$meta['quality']] = $meta;
+            }
+        }
+    }
+
+    protected static $metaList;
+    protected static $qualityHash;
+
+}
diff --git a/webapp/mt/HeroLevel.php b/webapp/mt/HeroLevel.php
index cee33a91..890ae5f5 100644
--- a/webapp/mt/HeroLevel.php
+++ b/webapp/mt/HeroLevel.php
@@ -2,7 +2,7 @@
 
 namespace mt;
 
-require('mt/AttrHelper.sql');
+require_once('mt/AttrHelper.php');
 
 use phpcommon;
 
diff --git a/webapp/mt/HeroQuality.php b/webapp/mt/HeroQuality.php
index bbbe2a3a..f2fbda7c 100644
--- a/webapp/mt/HeroQuality.php
+++ b/webapp/mt/HeroQuality.php
@@ -14,7 +14,7 @@ class HeroQuality {
     public static function getByQuality($quality)
     {
         self::mustBeQualityHash();
-        return getXVal(self::$qualityHash, $level, null);
+        return getXVal(self::$qualityHash, $quality, null);
     }
 
     public static function getRandAttr($initMeta, $nextMeta, $oldAttr, &$newAttr)
diff --git a/webapp/mt/Item.php b/webapp/mt/Item.php
index dd4f66ca..cc3602f6 100644
--- a/webapp/mt/Item.php
+++ b/webapp/mt/Item.php
@@ -77,6 +77,8 @@ class Item {
     const WEEKLY_BUY_LIMIT = 2;
     const TOTAL_BUY_LIMIT = 3;
 
+    const MATERIAL_CHIP_SUBTYPE = 3;
+
     public static function get($id)
     {
         return getXVal(self::getMetaList(), $id, null);
@@ -183,6 +185,12 @@ class Item {
         return $costItems;
     }
 
+    public static function isRandAttrItem($itemMeta)
+    {
+        return $itemMeta['type'] == self::MATERIAL_TYPE &&
+               $itemMeta['sub_type'] == self::MATERIAL_CHIP_SUBTYPE;
+    }
+
     public static function isBagItem($type, $subType)
     {
         return in_array($type, array(
diff --git a/webapp/mt/StrHelper.php b/webapp/mt/StrHelper.php
new file mode 100644
index 00000000..221dd9d2
--- /dev/null
+++ b/webapp/mt/StrHelper.php
@@ -0,0 +1,30 @@
+<?php
+
+namespace mt;
+
+use phpcommon;
+
+class StrHelper {
+
+    public static function parseList($val, $separators)
+    {
+        $values = array();
+        if (!empty($val) && count($separators) > 0) {
+            function parse($data, $separators, $i, &$arr) {
+                $strs = explode($separators[$i], $data);
+                foreach ($strs as $str) {
+                    if ($i + 1 < count($separators)) {
+                        $item = array();
+                        parse($str, $separators, $i + 1, $item);
+                        array_push($arr, $item);
+                    } else {
+                        array_push($arr, $str);
+                    }
+                }
+            }
+            parse($val, $separators, 0, $values);
+        }
+        return $values;
+    }
+
+}