diff --git a/README.md b/README.md
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--- a/README.md
+++ b/README.md
@@ -53,8 +53,10 @@ It's CC-NC. So DIY for yourself and for your friend, don't make money from it.
   https://www.lcsc.com/product-detail/Light-Emitting-Diodes-LED_Worldsemi-WS2812B-4020_C965557.html
 * TCA9548APWR (TSSOP-24) I2C multiplexer.  
   https://www.lcsc.com/product-detail/Signal-Switches-Encoders-Decoders-Multiplexers_Texas-Instruments-TCA9548APWR_C130026.html
-* 3x MPR121 modules, there're many types in the market, choose ones like this, and remember to **cut (unshort) the ADDR pin** which is short by default.    
+* 3x MPR121 modules, there're many types in the market, choose ones like this.  
   https://www.sparkfun.com/products/retired/9695  
+  Before solder MP121 module to the main PCB board, remember to **cut (unshort) the ADDR pin** which is short by default.  
+  <img src="doc/mpr121_cut.png" width="40%">  
   There's not enough space for the whole height of MPR121 module plus the lead pads. So you need to solder the module like the picture shows below.  
   First apply some insulation tape.  
   <img src="doc/mpr121_solder1.jpg" width="60%">  
@@ -62,9 +64,12 @@ It's CC-NC. So DIY for yourself and for your friend, don't make money from it.
   <img src="doc/mpr121_solder2.jpg" width="60%">  
   You can use the pins comes with the module, but you need to cut away the plastic pads.  
   <img src="doc/mpr121_solder3.jpg" width="60%">
-* 5x Sharp GP2Y0E03 ToF sensors, buy ones that equipped with cables.  
+* 5x Sharp GP2Y0E03 or ST VL53L0X ToF sensor modules, you need cables as well.  
   https://www.lcsc.com/product-detail/Angle-Linear-Position-Sensors_Sharp-Microelectronics-GP2Y0E03_C920270.html
-  <img src="doc/gp2y0e03_solder.jpg" width="90%">
+  <img src="doc/gp2y0e03_solder.jpg" width="60%">  
+  <img src="doc/vl53l0x.jpg" width="60%">  
+   You can use both of them in a same PCB, the firmware will identify each of them automatically.  
+  <img src="doc/tof_mix.jpg" width="80%">
 * 2x 0603 5.1kohm resistors (R1, R2) for USB.
 * 1x SN74LV1T34DBVR (SOT-23-5) level shifter (U8), if you can't find one, use a 0603 10ohm resistor (R3) as an alternative.  
   https://www.lcsc.com/product-detail/Buffer-Driver-Transceiver_Texas-Instruments-SN74LV1T34DBVR_C100024.html
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