diff --git a/src/MQUnifiedsensor.h b/src/MQUnifiedsensor.h
index 865399d..b7590e7 100644
--- a/src/MQUnifiedsensor.h
+++ b/src/MQUnifiedsensor.h
@@ -51,7 +51,7 @@ class MQUnifiedsensor
     byte _pin;
     byte _firstFlag = false;
     float _VOLT_RESOLUTION  = 5.0; // if 3.3v use 3.3
-    byte _RL = 10; //Value in KiloOhms
+    float _RL = 10; //Value in KiloOhms
     byte _ADC_Bit_Resolution = 10;
     byte _regressionMethod = 1; // 1 -> Exponential || 2 -> Linear