diff --git a/tools/esp8266/User_Manual.md b/tools/esp8266/User_Manual.md
index 774de905..7b0f4135 100644
--- a/tools/esp8266/User_Manual.md
+++ b/tools/esp8266/User_Manual.md
@@ -228,6 +228,7 @@ Gather user inverter information here to understand what differs between some in
 | tfhcm      | TSUN-350     |               | 1.0.14    | 2021           | 12-09           | 102       |          |           |
 | Groobi     | TSOL-M400    |               | 1.0.14    | 2021           | 12-09           | 102       |          |           |
 | setje      | HM-600       |               | 1.0.08    | 2020           | 07-10           | 104       |          |           |
+| madmartin  | HM-600       | 0.1.4         | 1.0.10    | 2021           | 11-01           | 104       |          |           |
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