diff --git a/src/NVMeSensor.hpp b/src/NVMeSensor.hpp
index 5d89d6a..7f2f114 100644
--- a/src/NVMeSensor.hpp
+++ b/src/NVMeSensor.hpp
@@ -21,8 +21,8 @@
 
     bool sample();
 
-    int bus;
-    uint8_t address;
+    const int bus;
+    const uint8_t address;
 
   private:
     const unsigned int scanDelayTicks = 5 * 60;