diff --git a/xResistorTransferBank/README.md b/xResistorTransferBank/README.md
index 917d7e1..5e1fd9a 100644
--- a/xResistorTransferBank/README.md
+++ b/xResistorTransferBank/README.md
@@ -3,6 +3,7 @@ xRTB is a relay switeable resistance box platform.
 
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 Design features:
+- I2C environmental sensor
 - Active guarding (20fA max)
 - Onboard resistor reversal switch
 - Onboard heater, keep resistors ovenized