diff --git a/HackRF-versions.md b/HackRF-versions.md
index 25b77a7..8c27158 100644
--- a/HackRF-versions.md
+++ b/HackRF-versions.md
@@ -1,3 +1,11 @@
+# HackRF
+## Official design (genuine and clones)
 The HackRF is the board under your screen (unless you are using it standalone) designed by [Great Scott Gadgets](https://greatscottgadgets.com/). Check the versions on the official [HackRF documentation](https://hackrf.readthedocs.io/en/latest/list_of_hardware_revisions.html).
 
-For the Mayhem firmware, check the [PortaPack versions](https://github.com/portapack-mayhem/mayhem-firmware/wiki/PortaPack-Versions).  
\ No newline at end of file
+## modification versions (not official)
+### var 1
+A version that claim added RF fronted protections, regarding the issue that the official design has a easy-to-broken LNA ([ref.](https://github.com/portapack-mayhem/mayhem-firmware/wiki/Usage-cautions))
+Note that we saw several users ([ref.](https://discord.com/channels/719669764804444213/737376558754300081/1241932352217939989)) and GSG official claim this modification weaken the signals (150 times as max) to become even not acceptable. ([ref.](https://greatscottgadgets.com/2021/12-07-testing-a-hackrf-clone/))
+
+# PortaPack
+For the PortaPack board (which contains screen), check the [PortaPack versions](https://github.com/portapack-mayhem/mayhem-firmware/wiki/PortaPack-Versions).  
\ No newline at end of file