diff --git a/Update-firmware.md b/Update-firmware.md
index f16b15b..6781a28 100644
--- a/Update-firmware.md
+++ b/Update-firmware.md
@@ -2,7 +2,7 @@
 Giving the fact that too much people still having issue reading this guide, please carefully read this chapter so you'll know basic concept of how to update.   
 **Please note that this chapter is just for making the concept clear, you still need to read all the content below for detailed guide!**  
 The basic updating procedure can be simply done by following two steps:  
-1. Update your sdcard content. This need you copy files around 1 GB, which is recommend to pull out your sdcard and use a sdcard reader on computer to copy files.
+1. Update your sdcard content. This need you copy about 2 GB files, which is recommend to pull out your sdcard and use a sdcard reader on computer to copy files.
 2. Update firmware + external apps. This can be done by following ways (pick one of them):
 
     * On a computer, enter HackRF mode, flash with a usb cable, then copy and paste external apps into sdcard.