diff --git a/RTL8218B.md b/RTL8218B.md
index 9eb4a479..cde340c4 100644
--- a/RTL8218B.md
+++ b/RTL8218B.md
@@ -184,6 +184,10 @@ Page | Register | Bits | Feature | Documentation
 0x42e | 0x11 | 15:00 |
 **Page** | **Register** | **Bits** | **Unknown SerDes - page unknown** | **Absolute 0x2261**
 0x44c | 0x11 | 15:00 | | This is some unknown PLL register - write 0x4000 to disable ring PLL
+**Page** | **Register** | **Bits** | **Unknown SerDes - page unknown** | **Absolute 0x2269**
+0x44d | 0x11 | 15:00 | | 
+**Page** | **Register** | **Bits** | **Unknown SerDes - page unknown** | **Absolute 0x2271**
+0x44e | 0x11 | 15:00 | | Some unknown register for fiber jitter 
 **Page** | **Register** | **Bits** | **Unknown filter register** | **Absolute 0x2310**
 0x462 | 0x10 | 13:12 | OFFSET_CALIBRATION
 **Page** | **Register** | **Bits** | **Unknown filter register 1** | **Absolute 0x2322**